One issue Brave has is the pro-privacy space it occupies. It shares this space with privacy zealots and those with an anti-Google agenda, and ends up falling foul of both groups.
This is a good point.
I am sure we can all agree that Firefox is probably one of the most privacy focused browsers out there. Problem is privacy is more of a philosophy, than a technical advancement one can see IMHO. For the record, I am very pro privacy, but I also use what works best for me. The issue they have is they can promote how privacy focused they are as much as they want....which is great, but when interacting/using the browser, what to people actually notice? Browsing speed, UI, memory usage, how it handles multimedia, PDFs, etc... Those are things people can actually see and notice, they cannot see privacy more or, less.
In the case of Firefox, while being very privacy focused, it was always a slower browser, that used up way too much memory, compared to the likes of Chrome. While Google is not the most privacy focused company in a millions miles, they did focus on things that people actually notice, hence why it over took Firefox. In saying this Firefox has still come a very long ways in many regards to address some of these issues, but unfortunately they really have not done enough IMHO. If they want to stay relevant, they need to wow people, which may mean taking risks, and starting from scratch.