Different instances have different ideologies. You can get a user on “everything-conservative” which blocks half if the federation, or you can get into a free for all instance which allows all. Big generic instances like lemmy.world do have a big problem on their hands, they have to make the bubble the common denominator of all users, which is hard to know.

Search by community is not working. If you go to search page, and select a community and click search, it will search in all communities anyway.

Someone would have to look at the terms and conditions. It’s possible there’s a clause like “anything you write is ours” in legal speak.