The reasons in this thread have been covered. Outdoor weekends here
under the Twin Cities TCA once had the near drone of light aircraft.
Now piston engines are rare & there mostly seems to be only turbine
traffic associated with MSP - even on nice days. At my favorite rural
Wisconsin airport I don't see anywhere near the traffic of say 5 years
ago. Mindless maintenance and medical requirements, TFRs, ridiculous
lawsuits, and now ADIZs continue to expand unabated. My family is not
intererested in flying or even inheriting the 172M I've had for 28
years. Student starts are way down elsewhere. The skies are
disturbingly silent.