Kinky seems to have become polite social code for 'perverse sexual behavior which I can't socially condemn without seeming a prude'.
But if you look at the public reaction to things like 50 Shades of Grey and Max Mosley's Nazi hooker caning punt, you'll see a lot of people are fairly vanilla in their sexual quirks.
Still seriously off limits is anything unhealthy, taboo under identity politics, or related to the four big Don'ts: animals, dead bodies, incest and kids. Apart from those its still a big blacklist: anything involving big age gaps between an older man and a much younger woman/girl, using gender charged words like 'whore', paying for sex (lol), watersports or anything do to with feces (ew), S&M (still), pegging (even in our enlightened era lol), feet, people who get sexually obsessed with buildings or other inanimate objects, transsexuals, pregnancy fetishists, race fetishists (like people who seek out pictures of African ladies in tribal gear etc), doggers (I have a male friend who is convinced if you like dogging, you are a misogynist), and in some cases anal.
Basically if you are a punter, you've probably done a greater range of stuff than 90% of the population has, or at least that they are willing to talk about publically.