Most scripts need to be executed in a posix-compliant shell

Simple. Just add #!/bin/bash to the start of your script and call it a day.

Or use #!/usr/bin/env bash if you're goated with the sauce. This won't work if you're not goated with the sauce.

Those who are goated with the sauce know what's up.

why use aliases (they exist in fish) when you can use abbreviations and your history isnt determined by whatever you set your aliases up as? If you change an alias, your history does not reflect that. If you use abbreviations, your history is perfectly usable

And also most scripts need to be executed in a posix-compliant shell.

That's why there is that shebang thingie in first line. Distributions like Debian use an entire different shell from bash for scripts: https://manpages.debian.org/buster/dash/dash.1.en.html