Firstly their search /discover was pretty terrible. I am sure that local groups exist, but searching for keywords mostly turned up communities with commercial angles.
Secondly even tho I only joined groups related to a very specific European location, every 3rd post in my feed is now bizzarely a scantily clad teen from Africa. I can dismiss these posts individually, but there is no way to tell Facebook's algorithim that it placed me in the wrong bucket, they provide no way to opt out.
If they really must insert random algorithmic content, Facebook already has all the clues they need to make it relevant, based on my searches and groups that I have joined. Instead their AI tried to play 4D chess with my preferences and outsmarted itself, serving me a horrendous swamp of teenbait slop.
Facebook is dead.