@dalias I think it would be feasible to have the apps excluded from that if they didn't recommend any instances with adult content. However, for usability / onboarding reasons, both apps guide users through making an account on a normal instance where adult content is allowed behind content warnings which they won't consider good enough. They would only potentially accept it if the default instance disallowed it completely.

I think what they do for review is joining whatever instance the app guides them to and looking for adult content, which is easily available and not moderated beyond requiring content warnings, so it has to be adult only. If the app didn't recommend any instance at all, they'd expect to be given credentials or instructions, and then it would probably be possible to avoid the adult only rating. It would still always be a risk they'd force it back.

There's no real logic to justify their different treatment of web browsers. It's just a special case because it's not expected for them to keep children away from web browsers but for other apps it gets treated as their responsibility. It's just their way of doing what's expected from them in the easiest, laziest possible way. Having any nuance is way beyond their flawed review systems.