Dude, just use discord. It’s easier, more accessible, and NSFW channels take one (1) “Yes, I’m 18” button-press to access them. Even on Iphones and junk.
Worried about the underage? Set up an “I am an adult” role and lock the risky channels behind it, and distribute the role after some sorta trust and/or confirmation.

Forgot to mention it’s also more secure, and by “more accessible” I also meant that people can use discord WITHOUT having to purchase a cellphone too.

But just remember, it's not a real gallery.