Isn't there some rule that any browser on iOS must use the native Safari engine? So if iOS Safari doesn't support something, there's no way for Firefox to add that support. It's basically just a skin.
Yes, but like I said, many other 3rd-party browsers have perfectly fine built-in adblockers.
Hell, you can install Firefox Focus (which is a ‘private mode only’ browser) and that does have built-in adblocking. More perversely, you can use it as a content blocker for Safari.
(No, other browsers using Safari’s engine do not inherit the content blocking)
I repeat: Mozilla is willfully choosing not to protect iOS Firefox users from ads. Plain and simple.