3 of the sponsors I've encountered (amazon, Google, temu) (I'll be honest, I don't pay attention often so there's probably others) are incredibly well-known for having terrible practices. Amazon exploits its workers, pollutes a bunch, and even works with israel. google sells user data, and also pollutes a bunch and works with israel, and temu potentially uses slave labour, as well as polluting a bunch.

I understand Mozilla needs money to operate but I'm sure there are tonnes of ethical businesses it could promote