problem with terminal on Mac os: (Dquote cmdsubst)

Problems like this are almost impossible to debug remotely because there are a lot of nuances to it, and you kind of need to understand the underlying issues to be able to fix them effectively.

First off, consider Terminal.app as doing NOTHING except for running another program known as your shell. It's the shell, NOT terminal.app that takes your input/commands and processes it. All Terminal.app does is take what you type and pass it to the shell for processing.

Now, for various historical reasons, there are many possible shells you can use. You might have heard of some of them - sh, csh, bash, ash, zsh, to name a few. Which one to use is largely a matter of personal preference.

Apple used to define bash as the default shell for Mac OS X, but they changed to zsh in Catalina.

Here's the kicker - you need to know which one you're using in order to fix your problem.

For example, the instructions you followed to change your path:

  echo 'export PATH="/usr/local/sbin:$PATH"' >> ~/.zshrc)

Explicitly writes the PATH command to your .zshrc file which is executed when zsh starts.

However, later in your post you state:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/uninstall.sh

so now you are explicitly running your curl command under BASH.

Guess what? BASH doesn't give two hoots what configuration options you use in ZSH. They are two completely different beasts. Therefore the first command (editing your $PATH) has no effect.

You need to decide if you want to use BASH moving forwards (change your Terminal.app preferences to use BASH rather than ZSH), or if you want to use ZSH (in which case execute your curl command in your zsh shell rather than invoking a new bash shell.

Confused yet? I did warn you.

No one can tell you the 'right' way to do this. TBH it's one of the bigger problems with homebrew (et. al.). While they do offer a peek into the world of UNIX executables, you are somewhat at the mercy of the homebrew guys and how they think/prefer things to be done. If you don't follow their model 100% (e.g. bash vs. zsh), that's OK, but you need to know enough of the gears/knobs/buttons to be able to tweak it for your environment.

That said, zsh has been the default Mac OS shell for a while now, so I'm surprised anyone is giving you BASH-specific advice, unless you're following an out of date support article, or that homebrew is still assuming bash.