Well, people have sadly learned the hard way that some community of certain kinks tend to be... how to put that politely, invasive perhaps? some (which I am part of) thinks it's needed to more or less (depending on the mood/previous grudges of the poster) politely remind people to not interject their kinks in other people stuff, I hope you understand that this isn't an insult or a judgement, but a mere reminder that what turn me on can turn you off and vice versa.
Futa alongside with Anthro/Fury and FF are the main offender in that category of "mainstream" smut invaders, in the more "niche" genre you have Pregnancy, Diaper/Scatt and Inflation.
Yes the words I use are rather harsh to define someone "innocently" demanding things, that's usually how it start, call me a cynic if you like but I've been around enough to notice patterns.
Regards.