Some sites don't work with ad blockers enabled. Yes, one can avoid those as much as possible, but some small maintainer of neat online services (no, not Google, Meta, MS, ...) also need their bills payed. So ads without tracking, i.e. collection of personal data, imho are a toad to swallow.
“Whatever opinion you may have of advertising as an economic model, it’s a powerful industry that’s not going to pack up and go away,” Holley said." ... “We’ve been collaborating with Meta on this, because any successful mechanism will need to be actually useful to advertisers, and designing something that Mozilla and Meta are simultaneously happy with is a good indicator we’ve hit the mark,” Holley believes.
Even if this is true, for Mozilla to take a position of capitulating to the ad companies and working with likes of meta to find what works for them is a sad day in the history of Mozilla. They need a new CEO who believes in a better internet. Until then, Firefox users might as well take the same position and move to a chromium based browser, where at least we get the speed and compatibility with web standards dictated by Google, if data mining and tracking is the only future left. What a sad state of affairs this is.