Comment by Etheryte
Vue is built on web standards just as much as Nue is. That is, web standards are there underneath, but both libraries add custom sugar on top. A good example is iterating over list items in Nue [0] and in Vue [1]. Neither is "pure web standards with nothing else", in fact it's exactly the same custom stuff, save for what keyword they chose to use.
In this light, I would say Nue's claims about standards first and only are pretty misleading, it does the same exact thing as existing libraries do.