1. Additional unnecessary launcher. I will accept the launcher that I bought the game from (i.e. Steam, for a game I bought on Steam)
2. Always online single-player game
3. Recurrent online activation game, especially one where the servers keep going down.
4. Not having a working pause function
5. Restrictions on when you can save

Hunger mechanics. I don't find them fun at all even in survival games.

Valheim (and to a lesser extent, Palworld with the feed bag) had it right. You don't need to eat to survive but there was still incentive to farm and cook different food for the buffs they provide

Micro transactions for non-cosmetic items, such as weapons, skill points, dlc, etc.. Especially on a game you already bought.

Oh, and adding a game breaking anticheat/DRM to a already launched game. Scrap that, anticheat/DRM in general. If you have to do it, at least do it right.

Overlays. Steam, my controller, mouse, headset, discord, my GPU all want overlays going at the same time. It's maddening.

Inability to invert the y axis.

Not having a save/checkpoint immediately before a particularly difficult spot. Retrying a boss a couple times can be fun, but not repeating the long, tedious trek from the nearest checkpoint.

When your walking speed is not matched to the NPCs you must walk with. W stop W stop W stop fuck it I'm just going to crouch maybe that'll work

Unnecessary crafting time. I don't need instant crafting for everything, but some games take it to far and it serves no purpose other than to slow down gameplay. Im playing through Scap Mechanic right now. If I want to make a car, I need to craft bearings for the wheels. Each bearing takes 30 seconds and I need at least 6 for a car. Not to mention the crafting chain of basic materials that you need to get the things needed to craft the bearings all take 20 - 30 seconds each. It can take a couple of minutes to craft from start to finish. I can't be waiting around all day for my stuff to craft.

The last boss of Paper Mario TTYD (original gcn version) has a huge unskippable cutscene you must watch every time you attempt the fight (and it's a hard fight)

The Legend of Zelda Skyward Sword has multiple, the most egregious of which are 1. Item pickup notification interrupts gameplay, and 2. They copied and pasted the worst boss fight in the game (like, the gameplay is poorly designed) so you have to fight them 3 times

End credits that can't be skipped or sped up

When games take away control too often, or for really minor things. Unsighted, a great indie game, was terrible for this. It would constantly rip control from you to slowly pan to a door opening or enemy spawning.

Cutesy games with violence as part of the gameplay.

I'm not talking about games which intentionally put these into a juxtaposition, like Cult of the Lamb or Binding of Isaac, but rather games which want to be cutesy, but also don't have any other idea for gameplay than making two characters bash each other's head in.

Nintendo is often weird here, like Advanced Wars 1+2 is literally a war game, but when your army invades a foreign city, the animation has a soldier just stomping on the city sprite, because I guess, this genocide needs to be child-friendly. Pokémon is also very weird.

Peripherals (USB headphones, mouse, etc) that try to install software suites EVERY. SINGLE. TIME. you plug them in. Razer products piss me off so much!

I consider it gaming shit list worthy because they target gamers.

Unnecessary dialogue, ESPECIALLY if that dialogue must be repeated ad nauseam in order to complete what should have been a bulk action. Animal Crossing NH, as much as I fucking adore that game, has got to be one of the absolute worst offenders in this regard.

Also, difficulty that isn't "tough but fair", and is instead "every enemy does 10x damage, has 500x HP, has their numbers increased by 5000x, and also you die in one hit." I'm exaggerating obviously, but my idea of a fun challenge isn't being given no room for error against overpowered enemies, it's the Souls approach; once I learn the patterns and flow of things, I should be able to almost play the game on autopilot. I still boot up DS3 all these years later just to relax, as I know the game THAT well now.

Fishing mini games!

I know they're very popular and people love them, but I don't like them at all! I hate the mechanic, in some games it feels poorly implemented (cult of the Lamb), and I just find them to be a boring chore.

When a game requires no arcade skills for several hours of gameplay, and then throws in some challenge/minigame that requires quick reflexes. Sometimes I only want to use my puzzle brain.

Unkillable NPC's, Bethesda style. Yes, yes I would prefer to miss out on content in favour of continuity and immersion.

Bosses that have almost heat seeking effectiveness with their attack. Meaning that no matter how far you go, no matter where you dodge, no matter if you're behind, they are going to hit you if you didn't hit the dodge exactly right to get the invincibility frame. Super huge and slow ass monsters that spin half way through a jump swing to get you behind their back is infuriating.

Menus inside of menus inside of menus inside of pause screens. I have the first Dragon's Dogma as an example. You cannot quit this game without going through three intro screens and their associated music jingle and animation.

Fake VR support.

I adore Subnautica for its PC experience, but it's the worst offender for this. It says it supports VR, but what it means is that you're supposed to sit in a chair with a mouse and keyboard while wearing your VR headset. WHAT. I spent 10 minutes trying to use my VR controllers before I googled the problem and found this out. Got a refund immediately. (I already got it free on Epic and bought the Steam version for VR)

Hey! Listen!

Microtransactions.

Microtransactions flogged in main menu.

Paying full price for a game to advertise ways I can pay more money for it, sometimes before I've even played a single minute of it.

Anything that unexpectedly triggers my motion sickness, especially chill puzzle games. (I am talking about Filament)

Sunset Overdrive. You can't just play the game, you have to be constantly moving, jumping, bouncing, grinding, even for objectives where it makes more sense to stand still and hold an objective point.

Trying to do anything other than constantly moving, jumping, bouncing, and grinding results in instant death for no easily discernable reason other than "the devs say so."

A lot of the ones in this thread cover mine, but here's the one no-one has mentioned yet:

No subtitles.

Fuck this. I usually play a game and watch a show or movie. I need to be able to read the lore. Making me whack up the volume because you're too lazy to add subtitles is beyond infuriating.

I love a good challenging boss.

But when bosses are just short of unbeatable it makes the vein in my forehead pop.

Shao Khan from Mortal Kombat 9 comes to mind. MFer was TOUGH to beat

3D first person jumping puzzles.