It's fine to criticize Mozilla for taking money from Google, but you would also have to accept that Firefox wouldn't exist without it. Google revenue is something like 80% of the revenue Mozilla receives in a year.

Google has now legally been declared a monopoly so they no longer have a reason to be paying Mozilla.

In fact it may be that Google is no longer allowed to pay Mozilla to make Google the default search engine on Firefox. If this is the case you will get to see how well they do without that money.

To be clear, I don't like that Mozilla is taking this money either, but the only way they're going to be able to stay afloat is by taking money from someone. Unless everyone who uses Firefox donates regularly to Mozilla.