You do not need both a JS and non-JS version. 90% of websites do not need to be fully in JS; the few interactive elements can be achieved with some vanilla JS added on top (that will degrade gracefully if not loaded, as the base content is still HTML).
I'll admit I'm coming at this 100% from the webapp angle. No project manager is going to sign off on that work NOR SHOULD THEY in 99% of cases.