I used Brave on mobile for a full week about a year or so ago at the suggestion of a coworker before realizing it gave me nothing over Firefox and added the bizarre crypto angle to everything.
This was during my (thankfully brief) crypto interest phase and I tried to see if I could accumulate any of the BAT coins the browser would give you for viewing ads...that never worked somehow so I accumulated zero, which was certainly one thing that led to me getting fed up with it and going back to Firefox.
Beyond that, the interface was weird, it was prone to crashes, and it was generally a hassle. 100% flash-in-the-pan cash-grab effort.