[sneak]

Malicious extensions, as well as the ability to block the browser vendor’s ads still pose a problem to these groups to be solved.

[techdragon]

Except Apple who don’t have the incentive of browser advertising and are currently selling privacy as one benefit of choosing their hardware (and by extension their software and browser [safari])

Mozilla make money from Google deals and so have outside incentives to not rock the boat too hard on this detail.

[contriban]

Keep in mind that Safari has enough restrictions that uBlock Origin developers decided to stop supporting it, so ad-blocking is pretty poor there.