In article ,
Larry Dighera wrote:

That kind of projection ignores the changes going on in how the total
number of passengers is being flown--in smaller and smaller
average-size units, thanks to the continued substitution of
narrow-bodies for wide-bodies on long-haul routes, of RJs for
narrow-bodies on medium routes, and (still to come) of more
fractionals and VLJs for short-haul airliners on short routes.
ATC workload (and hence costs) goes up directly proportional to the
number of aircraft in the system; but revenue goes up proportional to
the number of passengers and average ticket prices. The former will go
up at a significantly faster rate than the latter. This is completely
ignored in the CBO projection.

So by their own admission, the airlines are contributing to the very
condtion they are complaining about, ie... smaller jets clogging the
system.
But of course, they are their jets flying their passengers.

I liked that line in the ATA cartoon where the DC-3 says, "...they're
hogging our skies!"

The ATA message is so inconsistant and contradictory, but of course, the
general public never hears the whole story.