Soo.. the response to OP's post regarding the burden of maintaining systems built with JS frameworks is.. yet another unknown JS framework that will cease to exist in 3 months from now on?
The Framework is Rails focused in that 1) Event handling is setup by Stimulus (a basecamp js framework), 2) Rendering is done server-side, transparently sent client side via ActionCable with dom-diffing automatically applied.
It's a way of achieving a real-time app while still maintaining performance and reusing your Rails server-side views.