BeeWare and Qt are on different levels. It's like comparing a single guy on a scooter, doing a few deliveries on weekends, with FedEx. If you don't care about mobile, and you can deal with the licensing model of Qt and its wrappers, the choice is fairly obvious. Also, a lot of the knowledge around Qt is not really Python-specific, it's transferable to C++ (or the other bindings they have).

I like the guys behind BeeWare and they've done some very good work to address the awful Python story on mobile, but every time I try BeeWare it lacks a lot of functionality one would expect from production-ready toolkits. I'm sure things will improve with time, but I have a feeling someone with deeper pockets will eventually eat their lunch.