That said, we are slowly phasing out our React frontend for one of our apps page by page and replacing it with what we use over the rest of apps: Phoenix + Liveview. The changeset system for validations has proven itself time and time again to both be fast but also to handle many of the curly validation problems we might have. It also has barely changed since its release.
If you have a disciplined frontend team then you might be able to make it work. They have to be able to ignore the latest shiny thing that has come along, but if you don't then you'll have a team that is busy constantly upgrading to the latest shiny library rather than getting anything done.