Because Brave is just trying to build their own ad-network under the guise of being "privacy" oriented. It is a conflict of interest trying to get profitable selling user data while also claiming to block it. When first installed the their own ad and crypto stuff is enabled-by-default. Then throw in a few nefarious incidents, such as the affiliate link-hijacks a few years ago, and it is hard to trust them.

No browser is safe from capitalistic rot at this point.