Personally I'd prefer React Aria; I don't have the patience to try understand why suddenly everyone is rushing to adopt Base UI instead of Radix which itself was once suddenly the thing everyone rushed to instead of Stitches.

Having a library not in anyway related to that to me feels like a big pro.

I have found React Aria to be very good. I really like how its a set of hooks, a set of premade components using said hooks, and I like how you can choose bits of either approach for your own components. Some of the hooks are very useful.