More silliness. Pay developers enough so that they'll stick around. If they stick around, then you don't need to hire for talent in a particular framework or language. You can hire for intelligence, creativity, passion, drive, whatever... and invest in training people when they get there.
Jumping from framework to framework and language to language as the talent pool does is incredibly wasteful.
It's amazing FANG companies have any turnover based on that logic. Turnover happens for a variety of reasons... like global pandemics... you can't make a blanket statement like that and expect to be taken seriously.
In JS land there’s a ton of churn though for sure if that’s what you were thinking about. Not all of it though.
The point I am making is, using the current {shiny} tools might not be the correct answer (it could be though depending on the use case). Just use whatever gets the job done faster and then iterate. Some developers will start solutionising based on technology instead of focusing what is the purpose of the system and how it will help users. AKA: CV driven development :)
Turnover is a reality that can't be ignored. New people come in and now have to figure out something that reads like a stream of conscience. It isn't well documented, doesn't follow the latest best practices and doesn't support modern paradigms and uses outdated frameworks/libs, but works great.
The apps I build always take into consideration the talent pool my employer intends to pull from. The reality is that they (usually) can't hire general "technologists" that are proficient at all layers of the stack. If the project is something that only you will ever work on, then you can do whatever you want and this whole conversation is moot.