I don't understand the time zone issue. Even the macOS included Calendar app with time zone support switched on makes this a complete non-issue, and Google Cale

I don't understand the time zone issue. Even the macOS included Calendar app with time zone support switched on makes this a complete non-issue, and Google Calendar handled it pretty well when I used to use it too. I travel basically continuously, scheduling meetings in multiple time zones all the time, and as long as you enter the correct time zone when creating the event, everything works perfectly.