Oh, reddit, yes. Good point.

I don't use that; it's worse for your brain than any regulated substance. Kick your reddit habit while you can.

Google safe search: I've only seen this from my PAYG mobile phone, because I've never bothered to lift the adult content lock on that after more than a decade, and Google is the only place I've seen ask, actually. Even so it rarely happens.

Discord: the mere idea of being in an adult-content-related discord group is enough to make my skin crawl.

Worth noting that of these three, only one of them is a UK-only decision, as far as I am aware: Google Safe Search respects UK phone companies' default adult content block on PAYG. They are about the only company that does. Reddit and Discord have made this decision globally, have they not? Because there are US state laws too.