I believe the problem (As someone who works with fiction and has done NSFW equally) is not the fact that we can or not criticize fictional works regarding it's content. NSFW works that are oriented to the sexual appeal are, in fact, not oriented to be part of a big impact into the real world compared to representation, racism and other things.
But why would you ask? A lot of people have fantasies, fantasies don't necessarily mean that you want said things experienced in real life, with a real partner or partners, fetishes especially the ones that are either written or drawn are nothing but products that can be consumed by an individual that doesn't necessarily want to express nor needs to express it themselves. Meanwhile, racist portrayals, blackface, representation, Racial or LGBT stereotypes, social problems, economy status and other things... are way more realistic, and these topics can influence people in greater ways than a fantasize that has always been treated as something that has to be kept in secret and not be talked about, a taboo.
To put an example, many people love and adore stories like in Omegaverse, where instincts are excuses for non-consensual situations, power dominance, abuse of sub-genders, feminization, male pregnancy, and other things. However, rape, unplanned pregnancies, to dominate or be dominated, is not something that readers of said content want for themselves nor their partners, they don't want to be disrespected on bed or be treated brutally.
And that is the real problem with NSFW, people would assume the worst the second you mention or make content regarding a prompt or kink, indepedently if you actually like it, was a request/paid work or even practice.
Whenever I hear someone saying that "Fiction doesn't affect reality" or "Fiction does affect reality" I believe it is a projection of the person that is making that statement. You expose how influential you are the moment you make those arguments, or how terrified you are about the idea that a certain content that you do not consume may influence you in a way that you consider negative or "your worst outcome" which is totally fine but shouldn't be projected on others in a way that you in order to feel clean, have to demonize other people.
As well, I noticed that even when it comes to fights about racism, discrimination, and other similar topics the way people discuss is not as bad as when it comes to NSFW? Because whenever someone doesn't agree to the "better moral" the other person is approached with doxxing, suicide threats, assumptions of their sex/gender/identity, the word "virgin" being weaponized in a negative way contradicting the fact that we should pressure people to sexual intercourse or condemn them based on their libido and such. Actually, yeah, even if in the other controversies there is a lot of contradiction and hipocresy, I believe when it comes to NSFW is way more noticeable.
I may have stopped doing NSFW, probably like 2 years ago or something but I still receive some threats or insults through my DMs, and I have participated on controversies such as "whitewashing, pastels and harassement" or "Art theft done by a caucasian feminist from Argentina", so that kind of tells what actually triggers people the most, independently of their opinion.