Ruby on Rails is still the new Ruby on Rails. JS solutions still need another five years to catch up, unfortunately.
The data access layer in JS leaves a lot to be desired (especially compared to Rails)
React almost felt like a winner for single page apps, but there was never a great "flux" pattern to use, and now they've completely ruined that ecosystem with Hooks.
Also SPA's have become so big and bloated it's time to go back to something that you can build progressive web apps with like jQuery.