I'm curious about where you saw claims of Vue.js being a fully fledged MVC framework. Asking because I've always thought that Vue did a decent job of being forward about exactly what it is. Just reading the first paragraph of the guide (https://vuejs.org/v2/guide/):

"The core library is focused on the view layer only"

It seems to be pretty clear that it's meant to be a simple, easy to deploy, view layer only. I think it accomplishes that purpose pretty well. There are additional libraries (Vuex, VueRouter) which extend this core library into something coming close to a full MVVM framework, but those libraries are all maintained separately and not part of the core.