amazing. This used to be called /cgi-bin/ with templates and XMLHttpRequest (a Microsoft invention initially supported only in IE then adopted by everyone) and now it's suddenly a new technology/approach but with a new name so you're not ridiculed for using it? I gotta give them credit for revisiting server-side page assembling though; moving application logic and templating mostly to the front end was a HUGE mistake…
I don't think I've ever seen DHH or the Basecamp crew advertise any of this type of stuff as some groundbreaking new approach that nobody has ever tried before. On the contrary, I usually see them talking about how those old ways of doing web development were actually better in many ways, which is why they're pushing to move away from the current "everything is an SPA" approach.
And all this new tooling makes the experience much better than it ever was in the past.