An indication for Air/gnd transition would seem pretty pointless since you would have felt the bump.
Sorry, maybe you missed the inference for this particular thread.... a primary display of the mode the
system 'thinks' it's in? I'm sure most crew know when they are in the air and on the ground.
Hence, a half way house between the systems you have now and those legacy systems that control but don't always seem to inform...
So many important systems are dependent on this change of state, that one could argue for the crew having to be blind (or deaf) to not know it doesn't correspond to reality...