1) AI. This is the dumbest shit ever. It's not just a matter of excessively taking advantage of technology (I'm a computer engineering hobbyist), but it also obviously looks fake. You can't possibly achieve chemistry with virtual jello.
2) BDSM. It's good to have a little aggression in an act, but going beyond that is just overdoing it.
3) Gaping assholes. I don't need to see proof of your work. Numb, manufactured porn devoid of any and all genuine sensuality. At least when you are fucking someone's face there may be a shot at chemistry (no pun intended).
4) I love half of T-porn, but fucking a guy in the ass or getting him to suck it off is where I draw the line. There's no way I'd personally be a part of either of these things.
5) Toys. Keeping up with the theme of "fakeness" much like AI. Maybe there's something I don't understand about feminine sensuality, but between fucking yourself, getting some real dick, and fucking plastic/metal, the artificial is out.
6) Overdone ladies. My dick will excuse a bit of fakeness in the tits, I'm not gonna lie. If it works, great! But if I see scars or your face looks like that of an Irish-American Republican in his 50s with clown lips and symptoms of a drinking problem, I'm out.
7) Overtatted / overpierced. (Looking at you, Michaela Isizzu.) A little bit of piercing can be sexy in certain places. I like having the tat/pierce combo kept to a reasonable minimum, but if you look like a biker's cohort, ... I swipe left. (I made an exception for Annabelle Lane for her ink, but then she went through some further changes, and that was it for me.)
(Dis)honorable mentions:
8) Bad dialogue. I try to hack through the briar patch of abusive talk, but if you address to your stepmom as "stepmom", I don't want to be the one to tell you you have Alzheimer's.
9) Kathia Nobili's chainsmoker's voice. So it's fine if she just whispers.
.) I can't be turned on by the category of women who have gone thicc, but I won't put them on the list for any sort of judgment. I will give a shoutout to Kathryn Marie and Natasha Nice for their early work).
Call me vanilla, but I did make exceptions in some of these categories.