Python may be somewhat more popular [1] in terms of number of people using it (partly because a lot of Python programming isn't about shipping software and many Python users aren't professional programmers), but JS, Python, and Java, the three most popular programming languages today, are each dominant in specific domains, and none of them has a huge market share in the areas where the others dominate. There isn't a lot (relatively) of client GUI software written in Python or Java, there isn't a lot (relatively) of data analysis in Java or JS, and there isn't a lot (relatively) of serious servers in Python or JS.

[1]: https://www.devjobsscanner.com/blog/top-8-most-demanded-prog...