While you may be able to create amazing experiences in JavaScript, JavaScript still has multiple problems:
1. It is inconsistent [1]
2. It does not have many features that programmers love and other languages have.
3. It has a community that holds different values from what other programmers value themselves.
If people want to continue development in JavaScript, they can. But since JavaScript has a monopoly on the (fairly large) 'frontend development for the web' market, there will always be attempts to find an alternative.