Popular doesn't mean good. Check out modern pop music or American president (joke).

jQuery is ok for super simple sites, but modern interfaces becomes more and more interactive and complex. Attempts to organise some logic via imperative jQuery way usually turns into hell. So, first of all it isn't scalable.

Btw, I wrote an article how Vue.js can replace jQuery for "websites", not only for "web applications": https://medium.com/@borisadimov/vue-js-the-second-breath-of-...