Mozilla isn't just about the browser. It's about free and open internet. So of course they should be involved in authentication, search, messaging (mail, chat, and video), and secure dns. But they don't do any of those projects any more so whatever.
Which is contradictory with what they have actually been doing for a decade, which is pushing, pushing and pushing again for Web-everything and everything-Web everywhere.
Even the items you list after, in Mozilla strategy, were meant be implemented inside and around a single piece of tech: a Web browser, over a single protocol (HTTP(S)); also replacing classical libraries with Web-tech (that's now new since the interface of their products has always been based on some form of it, but they kept on pushing the pedal of webisation).
Given that the ad industry is filled by the kind of people who are vocally hostile to privacy (especially when it comes to "targeting ads"), this is a product without a market.
AIUI, web sites that host ads probably want the ads to be shown so they can get their money. And people who buy ad space probably want the ads to be shown so they can market their product or service. And maybe the ads will be shown if users white list ad networks that respect privacy.