Firefox

You are probably better off switching back to Edge, Opera GX, Chromium or even Chrome instead of Brave if you still want to use a chrome based browser. They have made some questionable decisions in the past.

BAT cryptotokens

So brave rewards you with their own injected advertisements with crypto, probably their most discussed feature. Could be a good idea if implemented correctly. But the real issue here is that they block advertisements and then add their own "privacy minded" advertisements back into the page for which you and they earn some crypto. So not only do you still see some ads with the default settings, now the site/content creators get nothing and brave earns money of your page views.

Creator donations

Speaking of content creators: At some point brave also had donation links on Youtube for those content creators that now earn less trough blocked advertisements and make brave money. Showing these donation links for specific creators, with their name and photo attached, with no opt-in or consent from creators themselves. Tom Scott even asked if they could refund everyone that donated to which they replied "Refunds are impossible". It looks like they changed the way that works after feedback though so no funds are being donated anymore unless the creator verifies in brave.

Affiliate links

At some point brave changed URL's from binance, even when typed in manually, directly to their affiliate link. They even publicly apologized after that. Which shows they are willing to change URL's to earn some money off you.

So yeah you could probably still use Brave even if you disable the crypto aspect but from actions in the past they have shown they really want to earn money off you. And they haven't hesitated to explore boundaries of what people find acceptable to get that money in the past. I personally wouldn't trust them to not do something questionable in the future either, crypto or no crypto.