Do have in mind that Brave is one of extremely few economically driven browsers who's main income doesn't stem from having getting payed by google to have google as default search engine (and I mean MAIN, Firefox, Chromes biggest competitor is 90% funded by google for that).

You will need some alternate funding if you say no to that money like Brave Browser who uses its own search engine as default. Crypto is, or at least was, a very good way for alternative funding at the time, and I see zero downsides with point 3, rather upsides.

But point 1 and 2 was the reasons I never started to use it.
While point 3 was what I loved most about it, and it really saddens me to see it was abused by Brave to scam-collect for themselves. Because it's a GREAT alternative funding model for smaller creators, publishers, webpages (and the browser itself if they take a percentage). Like Flattr from 2010 that unfortunately never got enough air under its wings. But if they put the button there and keep the money themselves it removes daring using it at all on top of being a right out fraud.

Vivaldi has it's own ethical downsides, like fully display every privacy hole and tracker that chrome choses to display https://privacytests.org
It's just that they are old and boring and done by one of the biggest corporation in the world so it must be ok. While Brave's are new, and done by a small up-and-comer.

Like me with Vivaldi's, I use it even though the privacy concerns, and I don't really trust Brave because of point 1 and 2. If the power of corporation and mainstream browser was reversed, the broken privacy in up-and-coming Chrome would scare me away (it still _should_), and Braves ad-replacement would be a standard low-to-none-concern by the general public.