Yes, you can develop highly interactive, reasonably complex web apps with jQuery, but then you would have to develop a lot of abstractions, guidelines and whatnot to keep the thing from exploding. That's pretty much what those SPA libraries and frameworks are.
About server side, IMO there's no inherent advantage on picking node over java other than the fact you'll have one less language in your stack(or not, since you may end up using TypeScript or some other compile-to-js language).
The will to learn vanishes completely.
I suppose that's fine for people who just want to learn something new every day. I want to make stuff, and the less maintenance it needs the better. Most of what's on the hype train isn't too appealing for that.