I think I can more or less say that we would not have been able to build what we have without RN. At least not with same budget. There is a large class of apps that would suck @ in a webview but can get by just fine in RN with 90% cross-platform code re-use. If you're already a team of experienced react developers the learning curve mostly just comes down to learning how to resolve build issues. And possibly expo can take care of that depending on your app. (anyone actually use expo for real stuff?)

With RN + React Web + [PaaS/FaaS] I feel like a lone dev can be dangerous theses days.

Doesn't mean Flutter or PWA's won't obsolete it eventually, and I'm optimistic about Flutter's approach. Just saying that there's a reason RN is a thing.