[fn-mote]

fish = "friendly INTERACTIVE shell"

Fish is my daily driver. I use it because it makes things I do regularly either easier, more memorable, or less error prone.

The primary use for fish is not scripting, afaik.

From a quick glance, nushell, like powershell, is strong working with pipelines of not-just-text data. That's better for your scripting/automation needs.

[Rant: Afaik, POSIX standardized what people did and agreed on at one point in time, warts and all.

For example, whitespace is a nightmare... in sh, var=$value vs var="$value", look at warts like "$@" and the ever-present annoyance of handling of paths with whitespace. I'm not even going to go look to see what of these are mandated by POSIX. Multi-OS scripts are different, doing something like Oil (oilshell.org) or PowerShell makes a lot of sense... ]