John Kulp writes:

They're two different things, both of which can improve delays. The
changed flight paths allow for more efficient TOs and landings, while
GPS allows closer flying.

How does this diminish noise to residents adjacent to airports (the only ones
affected by noise)?

That's exactly what it does. GPS is much more precise than radar
allowing closer spacing and straighter flight paths.

GPS does not track aircraft; radar does.

Uuh, it's better service. You can hardly fly large planes to small
regional airports which is what the smaller planes service. What do
you want to do?

Fly larger aircraft less often to the major airports, reducing fuel
consumption, pollution, stress on the environment, and noise.

Restrict the number of operators so the fares will be less competitive
and go up?

Regulate the nature and amount of commercial airline traffic, which is almost
the same thing.

They don't. It's just the opposite and seat loads are at historical
heights.

Flying multiple flights with smaller aircraft is much less efficient than
flying once with a larger aircraft.