RE: Question: How many get past the first trainer?
My observations over 30years...
About 40% even try long enough to solo. (THAT's depressing...)
About 60% of those who solo get a second plane.
About 50% of those who progressed toa second plane stick with the hobby more than 2 years.
About 80% of those who stay with it more than 2 years stay with it more than 5 years. (or if they were teenagers who left the hobby after 2 + years to go to college they will come back when they are over 40)