I was, and am, mostly on the side that argues that client-side javascript support can be assumed to such a degree that it can safely be considered requirement i

I was, and am, mostly on the side that argues that client-side javascript support can be assumed to such a degree that it can safely be considered requirement in a lot of cases. However, I do have some reservations of a more 'ideological' nature when it comes to requiring javascript when it isn't strictly necessary. I still believe one of the most powerful things about the web is the (relative) simplicity of the request/response server-side-rendering approach. There are so many ways in which a web page can be consumed (scraped, read-later-tools, etc.), within 'fair' boundaries of course. And this often falls apart because of client-side javascript. This is fine when it concerns a web-app that is specifically made for browsers (where ideally there's also a public-facing API). But for most other things it should not be necessary, and I believe it harms the possibilities of the open web. And quite often I find that it deceases the usability in general (back-button breakage, etc.). Of course, my ideal solution is both server- and client-side support, used appropriately, through something like React or PhantomJS.