Many comments here that I agree with, but I'd add that thinking purely in terms of commercial vs non-commercial is very reductive.

Mozilla is a not-for-profit company, and that matters, but they do engage in advertising deals and things of the sort. Non-profits do have less incentives for unethical behavior, but they don't have zero incentives.

I don't think we can only recommend non-commercial companies, although giving points for being so is good.

(Biases disclaimer: I like Brave, I prefer Firefox by a tiny margin)