I won't miss them, and neither will air traffic specialists.
They are often noisey, and serve little practical use.
From the air-traffic controller's perspective, they have
to spend almost just as much resources tracking small planes
as big ones, because collisions are deadly regardless
of the plane size.
I don't know what to say to plane affeccionados, though.
Perhaps "plane reservations" can be set up in remote
areas.