Does it simplify the build/ship process compared with React Native? The latter has a good coding experience (and real native UIs), but the housekeeping is a lot to keep up with. But at least some of that is intrinsic to the mobile platforms themselves
Yes absolutely. In fact I switched to Flutter precisely because React Native was so broken. Every time I upgraded, some package broke. Expo is alright but as soon as you try to do something outside of it, it sucked.
Packages didn't break on Flutter, releases are quite stable and preserve backward compatibility, at least generally.