If they haven’t made a public statement that they’ve stopped excluding atheists, why should anyone assume they’ve changed their policies?

For better multi-account container support, you might want to look at Sidebery instead of Tree Style Tab.

Is being an open nazi and rallying for hate speech legal?

Yes. Any law making that illegal would be unconstitutional. They’re assholes, but until they do or say something that is part of commiting a crime they still have a right to free speech.

Not since they started forcing minors to work on it.

I think you may have misspelled tweet /s