I've had quite the opposite experience there. I eventually settled on Brave because of my browsing habits. In particular I tend to have several windows of a browser open with dozens of tabs a piece and tend to rarely reboot my machine. Capping all this off is that I enjoy playing chess, which relies on millisecond responsivity. This [1] is a screen cap of the current performance usage of Brave. It's completely negligible, and hasn't been restarted for days. The higher memory processes are exclusively from pages I am currently using with extensive content loaded on them.
No clue about Safari but Firefox dies under these conditions, and I'm not interested in Chrome given not only Google but their 'vision' for the future of that browser including native anti-ad blocking. Opera was okay, but I enjoy the privacy features of Brave. Native ad-block, tracker blocking, etc that can all be customized per site in literally two clicks. Lion->Third Party Trackers for instance would allow me to enable third party trackers exclusively on Hacker News if, for some reason, I wanted to. Pretty cool stuff.
[1] - https://i.postimg.cc/Xq9fjFsc/Capture.png