From my experience some of these companies that are already using new state libraries still have code in older libs like Redux and it's important for them to hire candidates that understand how they work since they changed the way you think about state, and if you understand that it's very likely you'll understand the other ones.

It is really common for both Redux and React to be mistakingly labelled as frameworks by the people who don't really understand that these are libraries providing specific narrow piece of functionality leaving the architectural decisions and the overall application structure up to the developer.

Chat GPT seems to have statistical awareness of this fact, yet people generally choose not to figure it out

or Jotai!