Don't know why this comment was downvoted - it's the truest take here I can spot. The fact is that the factors that make one versus the other more preferable (the state and quality of frontend / backend tooling and environments, compute power and rendering capabilities of servers vs clients, round trip time cost vs responsiveness requirements etc etc) are continually changing over time and that's what's causing the back and forth swing, but lessons from previous iterations are generally learned.

I wouldn't be shocked if we sooner or later saw language-level support (think of something like Elm, improved) for writing "just" code and then later marking up which parts execute where, and the communications and state synchronization crud and compiling down to the native language is just handled.