Every table of friends that plays games together comes up with their own set of rules. These house rules reflect how these folks feel about the games that they play, and how they believe the standing, official rules ought to be changed (at least for their little corner of the world).
In Magic, this sometimes comes as a set of strategies that are disfavored. An example from our table: we do not use land hate (spells and abilities that destroy lands) or poison counter mechanics like infect and toxic. These strategies are valid, meaning they are legitimate and legal to use in Magic games. We feel they suck the fun out of the game.
That's often why house rules are made. There is a difference between the strategies that are legal to use and those that are fun to use. I will always push for the legitimacy of each deck archetype. But, some of the strategies that those archetypes employ are… uncool is the word I'll use.
Land Hate
[Blank] Hate is a title given to all sorts of deck strategies, all through the decades that Magic has been around. Hate strats revolve around disabling some specific element of the opponent's deck. Back in the prehistoric days of Magic's beginnings, plenty of cards focused on color hate, as in they were designed to foil cards of a specific color.

Color hate occasionally creeps back in with this or that set, but these cards have never been particularly common. They see use in Limited drafts, but don't have much applicability in Constructed. Each set has to supply cards for both Constructed and Limited, so the designers have to balance those goals.
In Limited, you're likely to see every color get used and thus peppering in these cards makes sense. Another way of looking at Divine Smite, for example, is thus; you're getting rid of something either way, but a subset of legal targets will be permanently removed instead.
Constructed games are mano-a-mano, and sanctioned games will sometimes go BO3 (best of three). Choosing a color hate card for your deck will either be of great benefit or do little for you, and it's likely to be the latter unless you're closely following the meta and lucky.
On to land hate. Land hate cards are those that are specifically designed to destroy lands, like Stone Rain. There are also cards like Dire-Strain Rampage which offer it as an option. Let's look at the differences.
Stone Rain here only allows you to destroy a land. It's as simple as it gets, and it comes from a different era of Magic. Conversely, Dire-Strain Rampage A) allows you to take out an artifact, enchantment, or land, giving you three supertypes to choose from, B) includes a compensation mechanism that allows the target’s controller to snag a replacement card, and C) specifies a steeper compensation if you used the spell to remove a land. This modern approach acknowledges the core problem with hate cards in general (their very narrow applicability) and with land hate in specific (it removes an important resource that you need to play the game).
If you have no mana, you cannot cast. No instants, creatures, artifacts, nada. Lands are your mana base, without which you will accomplish approximately squat. Sitting on your hands because you cannot do anything isn't fun, and being stuck there because your opponent put you in that position suuuuuuucks.
Playing against Control is different. You can outrun a mill deck, which takes time to grind you down. Discard decks can be tricky, but are doable. Countermagic decks can be beaten, either through cards like Vexing Shusher or simply by outwitting and outplaying the opponent. Whatever is happening, a spell of yours getting countered means that spell is gone; you can still cast more spells. Playing against land hate blows, because the removal is directly targeting your ability to play the game.
Poison Counters
Poison counters work like a separate life total. If a player accrues ten counters, then that player loses the game regardless of life total. It's a little more complex than that, in that you have time respond at instant speed and remove counters, but that's far less important than understanding that it sort of works like a second and equally important health bar.
I actually like poison counters. I think it’s a cool mechanic that is generally used quite well. I liked wither (and wish it would come back), I liked infect, and I kind of like toxic but wish it would just go back to infect. I understand how and why toxic and infect are different, but honestly infect was fine. I don't think the design space needs that degree of titration.
Though I may like poison counters, most of my friends don't. One of them started buying cards with toxic and infect. I told him that, if he breaks that seal, then I'll start playing more hard and fast Control. As the Zen master days, “We shall see.”

So, why don't players like poison counters? For one, they are hard to get rid of. Few effects that remove counters allow a player to be targeted. For another, infect and toxic are largely parasitic mechanics, meaning that cards bearing those keywords are confined more or less to the sets that spawned them. On the third hand, tracking poison counters now requires more math and mental tracking. That can be obviated, but it's still one more thing to adjust for.
All of this means that a creature coming at you with toxic or infect is a minor pain in the ass to deal with, and a deck specializing in laying poison counters on you is a warheads on foreheads situation. The hell do you do about that?
Poison counter decks require preparation to properly handle. Slotting in just a bit of removal might not be enough to manage what's coming at you. As such, poison counters are off-limits at our table. Though, they do work as a way around our next topic.
Lifegain Stall
This is a personal one. As someone who has both run and played against lifegain stall decks, I have come to the conclusion that they are not fun. A deck that only does lifegain to stall out a loss and wins only through attrition or relies on one or two copies of one card to win is just not a good deck. It’s the refuge of someone who is sore about losing and wants to grind out a win over 50+ card draws rather than attempt a better strategy. You could instead be using that lifegain to power something, like Dreadhorde Invasion, Treebeard, Gracious Host, Defiant Bloodlord, Trelasarra, Moon Dancer, and Bloodbond Vampire.

There are ways to use lifegain creatively as your core strategy. The original Ajani planeswalker had an ultimate that gave you a creature whose stats were just your current life total. Serra Avatar and Soul of Eternity both do the same thing in a creature card, and Sorin, Grim Nemesis utilizes your life total to go wiiiiide. These cards lend themselves to various strategies.
Boosting your life total beyond what your opponents can deal with and then doing nothing with it isn’t an invalid strategy, as in it is legal, but it seriously hampers play. That is definitionally uncool. If you want to prevent a state where people avoid playing with you and your deck(s), don’t do it.
Additionally, think of it this way. Let’s say you design a deck whose strategy is “I gain an asinine amount of life, pulling victory out of the reach of anything that isn’t running a mill deck against me or an ‘I win, you lose’ combo like Faceless Haven + The Book of Exalted Deeds.” Now, say that your opponent dismantles your strategy with a card that disables lifegain like my current profile pic, Tibalt, Rakish Instigator. If you can’t remove that card, your deck just died, possibly on Turn 3. The turns have tabled, and now you’re sitting and watching someone do their deck while you have nothing. Hell, a burn deck kind of has to run anti-lifegain cards in sideboard at minimum just in case there’s a lifegain deck chufting around.

That’s what it feels like playing against lifegain stall. You have nothing that you can do in so many circumstances, your options are quite limited. But, those options could very well counter the lifegain stall so completely that it can’t do anything against the counter. All someone has to do is throw a wrench between the gears and thus muck up the whole machine.
One of you is going to come away from the game feeling like the time spent would have been better wasted staring at a wall.
It’s an unfun strategy, firmly placing it in uncool territory. If the purpose of your deck is to gain life, do something with the lifegain. “Whenever you gain life” triggered abilities are a simple route to pulling yourself out of the box that such a design corners you into. You have to do something with the lifegain. The alternative is sitting across from someone for dozens of turns saying, “I gain another 167 life. Go.”
Alright, let's wrap this up. Happy Friday to those of you who observe, my condolences to my fellows that work this weekend, and either way stay safe if you're in the path of the storm coming up the east coast of the US.
In utter disbelief,
Sang1
Card images via Scryfall
1 I started reading the AI-generated sign-offs at Letters of Note. It's amusing, I love some of these. I'm going to start using random ones. Most will be as much a surprise to me as they will to you. Today's is #63/500, under the Angry category.