Brave uses its own Version of Chromium. This may be good on stock Android, but even there I would like to get an explanation why exactly Braves version of Chromium is better.
An important point here is, what a Webview wrapper can actually do for privacy and security. Can it disable Chromium features? Can it add own ones?
Coming from GrapheneOS I would not use Brave as Vanadium is very deeply integrated in the OS and uses advanced security features only available on recent Google Pixels like hardware memory tagging, as well as the hardened malloc, which comes preinstalled on GrapheneOS.
The developers discourage from using Brave, because on this specific platform Vanadium is simply more secure.
I and many more users would really love to benefit from Braves features though, like
Another benefit would be a much lighter app, faster updates and less RAM used. Especially good for weaker phones.
ALSO if Brave used regular upstream Chromium, issues like late security patches or other deviations in threat surface would be gone.
As I hope that GrapheneOS will get more and more adoption and media coverage, having a good Browser not tied to the developers resources, ideas and wishes would be very good. Vanadium will simply never have many of Braves features, let alone a Desktop client on all Operating Systems.