Looking at GitHub statistics, I would dare say TypeScript is pretty accepted: ht...

Looking at GitHub statistics, I would dare say TypeScript is pretty accepted: https://madnight.github.io/githut/#/pull_requests/2020/4

Out of all pull requests on GitHub in Q4/2020, 18.8% were JavaScript and 6.7% were TypeScript.

For reference CoffeeScript was at 0.25%. At its peak in 2014 it was at around 1.5%, when plain JavaScript was at over 20%.