They do enforce it as long they see it, so that pretty much as strict as they could be, and warning first is their policy so not every creator is scared away from their platform, and yeah if it was a smaller creator, they just instantly ban without warnings, same as they did to me, so they pretty bias if you are not JP and big creator.
Even my first Pixiv I got perm banned just cause I said I have uncensored stuff, without even sharing anything uncensored there, I simply just said that I have it on another site, and that's suppose to be a social media where creators share/promote their stuff and only by hinting that I make uncensored stuff they instantly bonk me. And the worst part is that they don't even tell you after they warn you once, they just said I brake their TOS so I had no clue what I was doing wrong and how to stop doing what they don't want me to do, I though it was the fact that I share realistic stuff, but only found out after I got perm banned that wasn't the case.
So yeah only JP site I use is Pixiv to share my stuff, I have the most views/followers there by far, but the issue is that most people that use Pixiv are not willing to go buy stuff from UniFans etc or something that is not built in Pixiv or non JP site and I lose a lot, especially since my Pixiv is pretty popular, getting regularly in top daily/weekly lists and I got quite big following but at best 0,1% of the followers from Pixiv actually support me on my platform. I'm afraid to even post my UniFans link there cos I don't wanna risk a ban.