It is a bunch of bullchit.
The airways are congested in major hubs not because of GA, but because the airlines and to a lesser extent, corporate aviation have flooded them in their own money grubbing, government subsidized money bleeding fiasco they call business.
If this passes, Mars is 100% correct, it will kill the dream that is aviation for all but the ultra rich and result in more accidents just so the general public can protect airline profits.