It wouldn't bring in their estimate, it'd kill the browser.
Right? This is what all these MBAs and supply chain efficiency experts never get.
The estimate does sound reasonable if it's an one-off payment. I agree that no one would pay that amount of money each year to keep adblocking from Firefox.
Maybe they'd still get paid $150M for that, while only having to barely keep the browser alive, with no user request, for illusion of non-monopoly.
Fewer devs, more bucks, big win for the execs on the short term.