[jai_]

I think your point (1) doesn't really match with what the rails devs expect.

37Signals have both their Basecamp and Hey.com products which act very much like a single page app but only using Turbo and Stimulus.

I think the rails devs believe that single page apps are overused and the majority of functionality can be done using just the provided tools.

[fishtoaster]

Yeah, the ruby community has a bit of an axe to grind with SPAs. Opinions range from the defensible ("JS is a bit overused, sometimes pure serverside rendering like Rails does is all you need") to the imo-ridiculous ("Pretty much no one needs an SPA and the whole frontend JS world is a passing fad").