I'm a CTO and I mark resumés down for having React on them. If you fell for that, what other rubbish are you going to fall for?
I'd rather hire an junior React developer than someone with such hubris.
This makes it harder to see this as something other than a developer-inflicted problem but for the fact that there are probably three groups of developers affected by this:
a) true-believer evangelists
b) resume-builders
c) innocent bystanders
There's no way to tell from the presence of "Framework X" on a resume where the developer falls between bystander and evangelist. Probably the CTO's point is that they do not like "Framework X", and cases of c) lack judgement and decisiveness for putting up with it?!
Anyway, funny to think about, especially in comparison to the playbook for changing the back-end frameworks.
Very few of your frontend candidates will be privileged enough to optimize for what you think is relevant. They exchange time for money, you know? Or do you know that.