zsh (because it is default on Apple), and bash when I cannot be bothered to translate to zsh.

I know what you mean by "terminal shell", but note that most of my use of the shell is from Emacs and not from a terminal (or terminal-emulating app).

The command line is fed to a non-interactive instance of the shell (bash in my case) using the -c flag, then the standard output of the shell goes over a pipe (not a PTY or TTY) to an Emacs buffer.

I mention this because HN comments tend to conflate the Unix shell with the terminal/TTY interface. (An additional source of confusion or subtlety here is the fact that Emacs can communicate with the user using a terminal interface, so I will point out that my Emacs communicates with me over the Wayland display protocol.)

zsh and fish