On a macbook pro, option key just gave me a ƒ symbol, both in Terminal.app and Ghostty. Anyways, if that was meant to be alt and it requires setup to work, then it's not worth the effort.
Terminal.app has a setting "Use Option as Meta Key" that needs to be enabled. It's under the Edit menu as well as in Settings > Profiles > Keyboard (if you want, you can click use Command-A to select all the profiles to apply the change to all of them at once). Ghostty will have a similar option.
Also surprised you haven't encountered this earlier, given it affects all usage of Alt in the terminal.
Also surprised you haven't encountered this earlier, given it affects all usage of Alt in the terminal.