Just because Facebook is big and supports something isn't necessarily a good thing. Their goals, resources and accepted trade-offs aren't likely the same as your own. For a large company like Facebook, handling large changes to a library aren't a concern because they have essentially limitless development resources. For small operations like mine (and maybe yours) these breaking changes can reduce the time you spend actually improving your product significantly.

For me, the instability and unopinionated nature of the group of technologies that loosely define "React" have been a real turn off. When answers to questions like "What language should you program in?", "How should you store your data?" and "How should I handle routing between pages?" all have no specific answer, it leads to a fragmentation of knowledge that in my past experience usually leads to a technology's demise.