This should never happen, the developers should not choose whatever technology stack or components they want for their piece of code, that's how Frankenstein started. But getting fired is reasonable in this case.
Agreed, but there must be more to this story that resulted in firing. You can't easily fire people for the issues listed here, at least in most civilized parts of the world.
I wish. West Coast of USA can fire you for a bad haircut.
Yeah, that's a little bit of the story that I left out - he also chose React without the normal team consensus on tech, so there was that, too.