The game is not “abandoned” but it is released and finished for it’s full 1.0 state. Just head over to Airport CEO 1.0-0 released and you’ll see that the game is receiving occasional quality of life updates.
Airport CEO is unfortunately not a live service game with a subscription payment model result an endless flow of new features. Hopefully there will in the near future come along a more complete airport tycoon style game that ticks all the bullets in your list, although I do believe that ACEO at least does have both baggage and economy and business class passengers! 
I myself will be waiting for that game at least, playing your own game doesn’t really scratch “that itch”.