From the google Shell Style Guide: "If you are writing a script that is more than 100 lines long, you should probably be writing it in Python instead. "
LOC alone doen't mean much.
I have a backup script in fish of 400+ lines of code because it tries to dump data out of different sources like MySQL, PGSQL, InfluxDB, /etc files and others. Just use what feels comfortable achieving the task.
https://google.github.io/styleguide/shell.xml