I think it's fair enough that libraries and frameworks change in ways that require your project to do some maintenance. I do not get mad when this happens with e.g. Qt. You may argue it happens a lot less frequently with Qt. Fair point, but Qt is very old compared to React. React 10 years ago wasn't even considered stable.
If you keep your dependency list short and make boring choices, your app may not still build with modern dependencies after 10 years of neglect. However, it will almost certainly not need to be entirely rewritten, either.
I think learning the fundamentals is good and people should learn to acquire less dependencies, but going as far as to say you may as well not use a framework because it will be gone in five years... I think that is hyperbolic.
If you keep your dependency list short and make boring choices, your app may not still build with modern dependencies after 10 years of neglect. However, it will almost certainly not need to be entirely rewritten, either.
I think learning the fundamentals is good and people should learn to acquire less dependencies, but going as far as to say you may as well not use a framework because it will be gone in five years... I think that is hyperbolic.