It's true that you need extensions on FF to have some of Brave's more advanced features. However, I consider this to be a good thing because you can skip their Web3/AI/Ads garbage and only get the features that matter like Forgetful Browsing (through Cookie AutoDelete) for a possibly lowered attack surface. Any Chromium fork, no matter how against big tech it claims to be, is still at the mercy of Google at the end of the day. Nobody is going to spend their time or resources patching Manifest V2 back into the browser after it's completely gone from the upstream.