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.