I even call myself an incel for the luls and no one has attacked me aside from one joke that I will never forget. No one seems to mind me being a NEET, either, or a hard determinist, or even that I often talk about my penis without any context.
I would object to the people reducing the effect of romantic relationships on mental health for young (age will make a huge difference, I am not talking about boomers here), lonely men (women seem to deal with this in a much better way, usually due to actually having a sexual/romantic history). Every single time someone like me gets a gf they're like "ok finally, bye, I'm recovering". And almost everyone that manages to recover usually at least has some previous positive sexual/romantic history (if not obtaining a relationship during or prior to the recovery), coincidence?
But I do agree that it's certainly no panacea and that mental problems like PTSD and shit won't go away by fucking.