See https://www.spacebar.news/p/stop-using-brave-browser
The TL;DR is that while the browser is technically fine, the people that own it are really fishy and are always trying to turn a profit, whether it be pushing crypto or discussing having their own ad network. They also use Chromium which means Google can slowly push things into it. You should use Firefox with Ublock Origin and tune the browser settings for privacy. There are also forks of Firefox tuned for privacy but I don't think most people need it.