Yep, this is exactly what I do with my Surface - except then I do code on it, which is why I picked it instead of an iPad pro. This one device has replaced my MacBook pro while still letting me sketch and draw and annotate.
I’m sure there are some customers / use cases where those differences aren’t a deal-breaker. Personally I really appreciate it. I have been very impressed with the iPad pen input. It’s clear their hardware and software engineers collaborated closely to make a really impressive device and experience. (Again, as long as you mainly are using pen input.)
It’s possible there’s other software out there that does a better job than Microsoft’s first party stuff or the couple of third-party apps I tried.