A smart tester suggested that, if you disable all airplane doors in AES (except the main passenger door, most likely), AES will not display ground vehicles, and can be used just to operate the jetway.
However, this trick is valid only if the airplane is supported in the GSX internal database, which has the priority over the intelliscene.cfg .
If the airplane is unknown to GSX, it will try the intelliscene.cfg file, and if there's none, it will try to do its best with the airplane.cfg+simconnect. This means, if you use the "disable doors" trick to disable AES vehicles on an airplane that GSX doesn't support directly, the doors will be disabled for GSX too.