Meteor.js beats rails in terms of productivity. Also it's in most cases more performant (node vs ruby thing). It requires some re-learning of how to model your data (document store vs relational data), but in most cases it's worth it.

Also soft realtime is the default, shipping mobile/desktop apps aside with your webapp requires little to no code changes, and even offline working apps are doable with ease.

Rails was fine 10years ago and popularized many paradigms when it was important... Now the world moved on and requirements changed heavily. No bad rap for rails (it paid my bills for many years!) but it left the path of innovation and is now mainly on the maintenance road and trying to catch up and thats it IMHO.