I'm working with Rails for 17 years now, still love it and still prefer it even for the frontend. It give you all the options to separate your code without the head of your files becoming a unnecessary long list of `includes` like I see in the angular app I have to work on for a client. I don't see a disadvantage in splitting logic and markup for the frontend, it allows you to test the logic independently and normally when you hunt a bug you should know whether it's in the markup or the logic. Tracking down a bug thus becomes more easy.

I've written my fair share of far too long ruby methods, 200 lines and more, but those are truly my fault. With a more granular unit test regime those can be prevented.