> you have to make sure that important functionality doesn't break when it's applied.

This feels unnecessarily conservative for a browser trying to achieve literally any market share; nobody's got only Brave installed and those who have it at all are those most likely to understand if a site is broken because of its blocking measures.

If Brave isn't going to be the one to push privacy features over compatibility, who is? I mean, you didn't name it "Caution".