Google's only reason for keeping Mozilla on life support is to avoid the argument of being a total and complete browser monopoly.

Firefox's global traffic market share is less than double digits [0] and is less than 5%. Google technically doesn't need traffic from Firefox and Google is roughly paying half a billion ($585M) a year for it. [1]

[0] https://gs.statcounter.com/browser-market-share

[1] https://stateof.mozilla.org/pdf/Mozilla%20Fdn%202024%20-%20A...

This doesn't make sense as Edge is a bigger browser than Firefox and competes with Google in the browser space. What Google pays for the traffic is less than what the traffic is worth (Google profits a lot too).