On Friday, March 3, 2017 at 8:45:59 PM UTC-5, WB wrote:

Given that today *everyone* has plenty of potential exposure to the reality of
flight/pilots-required/etc., exposure would seem to be less "the main" entry
barrier, than "something else," insofar as the health (or not) of US general
aviation is concerned.

The above is from the perspective of an SSA member since '72 and an EAA member
since '79.

Bob W.

Just my opinion, but I think the main entry barrier is not at entry, but at the point about 2/3rds of the way to solo. The trainee just gets tired of spending days at the airfield and getting only a couple of flights with an instructor.

There is some real truth to WB's observation for some people.
In our area a student has the option of flying with our club or going to a commercial operation 10 miles away.
When a student is not happy with waiting and sharing resources we suggest that he or she try the other operation. Some do and some stay there. Most don't due to the difference in cost, which is about double.
We run a training operation all day with two 2-33's staffed as required. Most students get 2 to 3 flights a day.
If someone is time constrained we suggest they get there at the start of operations and we'll get their flying in so they can get to the soccer game, or whatever.
Interestingly the people who act most time constrained can't drag their butts out of bed in the morning. They expect to be customers, not club members. Experience shows they are much less likely to stick with it and be long term participants.
We do put extra effort into having waiting member help out which makes the time go quicker.
FWIW
UH