Mozilla has had missteps for sure (like almost every other browser company). but the MVP is uBO (which Firefox still allows). Even if Firefox adds that in by default (which suck), uBO allows you to block outgoing traffic to these 3rd party sites.
Firefox vs uBO is cat and mouse game. Cats always win.
uBO creator, gorhill, should write his own, $10 one-time purchase, browser app, this will be the end game :)