IMO if you want to run PostgreSQL, React and GraphQL with the least amount of friction and decision making, RedwoodJS is great choice.
> How would you say an opinionated framework like this works in the medium to late maturity?
If you run a frontend-heavy and/or TS/JS shop and don't mind the tradeoffs of something like Ruby on Rails, then I see no limitations to building whatever you want with it.
> Is it easy or even possible to switch out components with more "enterprisy" solutions?
Not sure what that would look like, so I can't comment.
For some usecases, quick bootsrapping is incredibly valuable - eg an early-stage startup.
That was the historical case for Rails: quick to get started and not too bad to maintain/expand as you grow (it got better about later stages in the later years as the ecosystem matured). That's a tradeoff that can make a ton of sense when you're starting a project that has a good chance of not existing in 6 months and where every day of initial productivity is incredibly valuable.