It's a fine architecture, true. Maybe you're thinking of AirBNB, they popularised this "holy grail" model (http://www.oreilly.com/pub/e/3009) since around 2012.

Twitter did have to backtrack from the #newtwitter pure client-side model. Serving a 140-character string shouldn't require a 1+ MB payload. So maybe they server-generate their pages this way too now.

I agree with you that it's a misuse of the word, but for some reason a bunch of javascript developers have adopted it in the sense of having a webapp suite that spans both a node.js server-side environment and a browser client-side environment, and being able to migrate code between the two parts of the app. Go figure.

http://www.oreilly.com/pub/e/3009