Another dilemma for website archival, then. It'd be cool the Internet Archive came up with some JS shim to render websites how they were supposed to look.
(Enough so that if I find a website with JS required, I'll usually defer first to opening it in Archive.is, though of late the endless CAPTCHAs are somewhat chilling the enthusiasm of that.)
I've started opening Bloomberg articles in archive.is since they started not serving the article content. (And, presumably, loading it later through javascript?)