I think people are implying that Google told Mozilla to drop Servo, to make sure Firefox wouldn't leapfrog Chrome. And since Google funds Mozilla almost entirely, Mozilla had to comply.

Almost no technical aspect of Firefox have anything to do with how much money Google pays them.

Mozilla is basically paid by Google to have a multi-platform non-Blink browser around they can point to when accused of being a monopoly.

Having a quality browser is not required, merely it existing. So why waste money on novel web engine experiments when you can have AI conferences in Zambia?

How do you think Firefox is making money, since it has no payed features? Hint: it has Google search as the default search engine.

Nope it comes from Google.