The problem was not that they used shell scripts. The problem was that the people writing the shell scripts were just bad programmers. If you hire a bad program

The problem was not that they used shell scripts. The problem was that the people writing the shell scripts were just bad programmers. If you hire a bad programmer to write them in Python, they'll still have tons of bugs. The shell scripts I write have fewer bugs than the Python code I see other teams churn out. But that's because I know what I'm doing. Don't hire people who don't know what they're doing.