Comment by NoahZuniga

> Google pays Firefox ~$500M/year for 2.5% market share, 65% market share should get a healthy annual payout for default search status.

Google gets other value with this besides being the default search engine. Keeping Firefox alive makes it so that Chrome is less of a monopoly.

> and an aggressive fork at some point

Maintaining a browser engine is a lot of work. With no clear upside, no one would invest the work in maintaining a fork. Related to this, Microsoft gave up maintaining a (partially) separate browser engine for Edge, and now just uses Chromium