Do you mean the Nazis? They're blocked because they are Nazis.

If you mean the porn instances, they're full of spam and fill your feed up with crap. The reports are tiresome, also. If you want that content, it's super easy to have an account on one of those instances as well as here.

As to "normal Reddit", this isn't Reddit and we don't try to be. Apologies, but they don't guide us at all. And most users like it that way.