Until your LTS OS gets to end of life and you need to switch to the next one which conveniently deprecates old python versions so you have to rewrite everything.
Why use system Python base environment for production stuff, especially knowing that it will EOL eventually and mayhem may follow? Again, pin your environments using conda, pipenv or whatever else, in which case your base Python version wouldn't matter.
Well if you're using ROS, you get to choose between the two extremes of C++ or Python. It would be great if everything was in C++ to be sure, but ain't nobody got time for that, especially not the cheap results-quickly company I work at.