[skydhash]

A browser is there for retrieving documents on behalf of the user, not to add its own spin to it. It's already bad with everyone and their dog wanted to abuse the user computation power with "apps" where it should be simple forms and listing.

[nine_k]

Ad-blocking and reader mode is "adding its own spin" (or rather removing that of the original).

The problem is not that a browser should not act intelligently on behalf of the user. The problem is that what is usually called "AI" is known to sometimes act erratically and invasively, and also consume a lot of (local) resources. That is, the "AI" is not trustworthy enough. And the key feature of Firefox for much of its audience is that it's more trustworthy than the browser named after a particular shiny transition metal.