I do think that React has a chance at beating this trend though. As Rails became more and more esoteric with DSLs, utility functions, and `method_missing` hacks that make complex existing monolith codebases nearly inscrutable, and microservices became a preferred way to "throw bodies" at similarly complex codebases, it's not surprising that people started moving away.
React's ecosystem, on the other hand, has embraced strong typing (and alongside it, tooling that lets you drill deep into any method you see on the screen), and it's fully compatible with teams working on discrete backend and frontend components. It's not likely to disappear any time soon, the same way jQuery hasn't disappeared. Yes, it adds a performance cost, but so long as Zawinski's Law holds [0], functional state-to-display-object transformations will continue to be the paradigm, and React continues to lead the pack there. And if new display object abstractions come into play (say, React Native in-browser rendering widgets on the GPU directly via webasm or new browser-specific APIs), React can and will adapt.
As people exited Rails, the cost of maintenance has gone up... since you have to pay a lot to get someone writing Rails now.