[alsetmusic]

Compatibility with older devices that aren't eligible for recent OS updates, I would assume?

Or, if the person is like me, they're more comfortable in Bash after years of it being the default. Hacking around in a less-familiar shell seems like a bad idea if it's optional when deleting data, regardless of what's currently the default. (I realize that zsh can execute commands with Bash syntax, that's not my point.)

[chasil]

It's actually more appropriate to install dash, and write the script with that.

When this is done, it will run in all the shells, because the script becomes POSIX-compliant.

[plorkyeran]

Making a macOS-specific script which does not make sense to run anywhere else portable to other platforms is entirely a waste of time.

[chasil]

Portability between bash and zsh is a waste of time?

Wasn't a previous argument that legacy Macs should remain supported if possible?

smh.

[duskwuff]

zsh has been available in every version of macOS since 10.0 - there's never been a version where bash was installed but zsh wasn't.