I like being able to SSH into a fresh Linux box and feel at home, but at some point, they'll be so different that I might as well permanently switch to Zsh.
I keep hoping for Apple to adopt Fish, last I heard the guy works there, and it's totally Apple's thing to have its own shell. It would be fun at least.
Realize that if your personal account's shell is pointed into the homebrew installation in /usr/local, and you implode homebrew or wipe /usr/local, you won't be able to start a terminal until your shell is changed or the binary exists. Solving this without Terminal.app being able to launch is a minor annoyance.
#!/bin/sh
for shell in \
/opt/local/bin/bash \
/bin/bash \
/bin/sh
do
[ -x "$shell" ] && exec "$shell" -l
done
echo >&2 "ERROR: No valid shell found!"
read -r -s -n 1 -t 10 dummy
exit 1[0] https://www.quora.com/What-is-the-reason-for-some-of-the-Lin...
Apple takes issue with patents-related wording in GPL3 and doesn't want to be subject to GPL3 (while they're OK with GPL2). Hence not distributing GPL3-licensed software.