Be able to use any language for the front end is great thing, but I have a concern for existing frameworks/libraries. If someone build a great tool, lest's say

Be able to use any language for the front end is great thing, but I have a concern for existing frameworks/libraries. If someone build a great tool, lest's say the equivalent of D3.js, in Java; I don't see a way I can use it in python without having to write a python API for that library. It's not necessarily bad. The first advantage being, that hopefully people are going to stop recreating new javascript frameworks every 2 months.