Mozilla had the opportunity to do this. Or to do something like this. GNU Taler is a thing.

Mozilla pulled a sneaky trick on his community: convincing us that context sensitive advertisement needs to be collected by the browser. It's on the back of another trick: convincing people that they can only make money through ads.

A few months ago, Mozilla officially became an ad company, so any claim they make about privacy has a clear conflict of interest with their own monetary gain. By selling advertisements as a necessary evil, they can sell you the cure.