A game has a really bad chance with me, if its world is broken into little floaty pieces. I hear great things about COE33, but the game world is a major turn off for me, all bent and broken up. Same goes for DMC (even though that game had other problems). To a lesser degree this is true for the new Control game aswell, with the gravity bending mechanics, running on the side of buildings, with one structure standing up right and the other sideways (I loved Mario Galaxy).

Political agenda's/forced crap and massive patches/games not on disc or cart.

Instant no buy.

Soo kinda like all modern games nowadays.

Retro ftw!

The obvious one is of course bullshit DRM or monetisation. The strongest example of games that I was really interested in but just skipped because of DRM are the new Hitman games. Online requirements for that is just garbage.

I also must say that I check howlongtobeat to see how much time I would need to make it through the core game. If it is more than 50 hours, it is an almost guaranteed pass, I don’t have time for that. Is it more than 30 hours, it will need something else to excite me. This is one of the reasons I haven’t bothered with the Persona games or a lot of other RPGs, it also isn’t my favorite genre in general, but there are some masterpieces I can get behind.

Some other types of games that I am usually immediately turned off by are the rogue-likes, make your own fun games (Minecraft etc), realistic sports games. Also most racing and fighting games post seventh gen.

Come to think of it, there is really very few modern games that do excite me, lol. For retro games I have a broader taste, but for new stuff I mainly enjoy horror/survival-horror, a couple of platformers and indie titles I feel really try to do something unique (Her Story to give and example).

Anything dubbed "Souls-like" or with a heavy multiplayer focus. And, of course, any and all GaaS titles. 

If a game is made for older consoles and the cartridge runs at the wrong voltages and slowly cooks your vintage game console. 

Game-Key-Card
Code In A Box
Half the game is on cart, and the other half needs to be downloaded from the internet.
The game is a 1MB stub and requires you to download the remaining 99 GB from the internet. 

Over $100 worth of Microtransactions in the Microtransaction store. Some games, like Smash Ultimate or Ateleir, are really light with their microtransactions. But any microtransactions in a game is enough to dock it 10 points. So if a game gets 85/100 on OpenCritic, but has MTX, then it's a 7.5 for me. A game with heavy microtransactions like MK11 is more like a -20 modifier to the OpenCritic score. So for me, MK11 is 60/100 bottom of the barrel trash. I love Monster Hunter, but Capcom has monetised it so much that I haven't bought a new MH game since Rise. I am fine with MTX that only speed up gameplay such as how Dragon's Dogma 2 or DMC4 did it. As long as they don't intentionally make the game more tedious and then try to offer up a MTX as a "solution", I'm fine with that sort of thing. It takes just as much time to unlock everything via grinding for Red Orbs on the 360 version of DMC4 as it does in the Remaster, for example. So that's fine. 

Any AAA game that doesn't have a physical release. 

Exclusive to Xbox and/or PC. 

A few things off the top of my head:
- Camera perspective limited to first-person
- 4k 60fps not supported (ideally should be 4k 120fps nowadays)
- FOMO featured in the game

There are a couple more mentioned in the last couple of posts above mine that I agree with too.

Games that force you to do side quests to progress the main story. Still haven't Witcher 3 or MGSV because of this.

I see a lot of posts about politics in gaming, foced agendas. For me, a political or socio-political topic in a game is fine. I only dislike it, if the topic is presented in a finger wagging, lecturing way, instead of letting me make up my mind about it myself. Present something, fine, but don't try to convince me of your opinion about it.
A huge problem for me is also when the political messaging stands in the way of good storytelling. Like forcing something in sideways making characters unrealistic / unlikable, or constantly coming back to the topic instead of focusing on character growth and plot development, or making character motivation unrealistic because everybody except the most deplorable would have the "right" convictions, even if the topic at hand is a fringe phenomenon only a handfull of people actually believe in. Or when old timey fantasy worlds look and sound like modern day with all the trapadations and social issues of today included.

And, of course, if I happen to disagree with the socio-political agenda in a game, even if it is done tastefully, it has a bad chance with me. For example, if a game tries to present nazi ideology as sympathetic, I won't like it (this is just an extreme example, but the sentiment would hold true for a lot of issues with me).

Length is a turn off. Octopath 2 is something like 60+ hours, I would get it if it were 20 to 30 hours. I rarely buy super long games.

Social elements is also a turn off. Can't stand stuff like Persona with all the school room teenage stuff.

Edit

I am also refusing to buy Alan Wake 2 till it hits Steam, which could be never.  

When it comes to shooting games, the absence of gyro controls is the deciding factor that makes me skip the game on console. I can't stand stick "aiming."