Programming language choice is determined by the task at hand. If you want to create frontend web apps, it’s JavaScript/ Typescript. If you want to write an OS, it‘s C/C++. If you do data analysis, it’s R/Python. Apple ecosystem? Swift. You can continue the list. By looking at domains and dominant languages. What resources are there for your domain, what have others contributed to, what libraries/ packages are there, what’s the mindshare, etc