[vectorpush]

Rails was designed at a time before angular brought the SPA into fashion. SPAs manage state and template rendering on the front-end, so much of the Rails machinery becomes unnecessary. You can still use Rails to implement your JSON API backend, but the simplicity of something like Sinatra is often preferable since you're increasing the complexity on the front.

The node+react+webpack combo gave web devs the power to process application states and render the UI on the front-end and the back-end using the same code; a feat that is not possible at all with Rails pushing it a little further out of fashion.

Of course, the SPA suffers plenty of criticism, and Rails is still a popular choice with and without an SPA on the front-end, but I think it's fair to say that Rails is no longer the "fun" way to do things (though the most fun doesn't mean the best business or engineering solution).

[jholman]

I agree with all of the major points of your comment, but I have a quibble:

> Rails was designed at a time before angular brought the SPA into fashion

I dunno that Angular is the relevant point here. Rails (late 2005? I think?) post-dates the public existence of Gmail (public April 2004), a wildly popular SPA. It also post-dates the existence of Google Maps (early 2005). The famous blog post by Jesse James Garrett that coined the acronym "AJAX" is also from early 2005.

The thing that Rails does well was already largely-obsolete before Rails was open-sourced. (Though that is one state-of-the-art buggy whip! Very impressive!)

[vectorpush]

I absolutely agree that the SPA was already a thing before angular, in fact, angular was specifically designed to wrangle the general design concerns related to building SPAs and doing so sold the distinct concept of the SPA to many developers.