Right. After you've spent 10+ man/years developing an app based on React / other lib with similar restriction. "stop using React" is fine advise for small projects that can be rewritten in few months by few people. For very large projects the cost of stop using / rewrite could be huge.
Exactly. If you're actually in a legal dispute with Facebook, the cost of rewriting your frontend to not use React is minimal.
It's not like React is a massive library with a huge surface area. Even a fairly complex application could be migrated to an alternative like Vue.js if the need arose.
