discord has to do this to comply with international laws, they've made it very unintrusive. they estimate your age based off information you've given them (not including messages and the like), not put you in the teen category by default. there are a lot of bad things discord does, but i dont think they're doing this specifically out of malice or greed. it feels very clear to me that they just need to comply with age verification laws and didn't want to intrude anyone else.