I fear this could create website silos. Where certain webpages can only be accessed by a given browser because visits from that browser could be more profitable than running ads. But this is probably a long shot...
Since Scroll is a separate entity, they can freely make the same extension available on other browsers.
So all the heavy lifting is being done by Scroll. Firefox Enhanced Tracking Protection (ETP) is the "second half" of the offering here named "Firefox Better Web with Scroll". But ETP is just a regular feature of Firefox now. So the real thing that Mozilla is adding here is their size. By attaching their name to it, they legitimize the concept of replacing ads & trackers with subscriptions and payouts determined by engagement not clicks. Though, I might wish they had come up with a catchier name.
This is GREAT! It's something I've wanted for years now! [1][2] Thank you Mozilla, for daring to approach the biggest problem facing human communication this century. I've never heard of Scroll before, so I'll need to do some research, but I'm just happy that someone is trying this again.
[1]: https://news.ycombinator.com/item?id=9721917 [2]: https://news.ycombinator.com/item?id=11622050