From my understanding brave is decent for privacy (not great. Just decent). It has a lot of issues though with the founder being a right wing supporter who has opposed human rights and had some covid opposition. It also has had issues like when you used the inbuilt tor system it leaked DNS queries making tor a little useless and ruined a lot of faith people had in them to make decent privacy software. It has also been very cryptocurrency forward. It also stole crypto from a few people through a “bug”. Basically it isnt that brave is currently proving they are a shit browser but there are several issues in the past and controversies that make most privacy focused people not trust it.