Like so many things it all comes down to disposable income. Step back 40 years and there were no IT people in aviation, the major source then was the motor trade.
The statistics are not good, look at the CAA website and you can see the number of licence issues across the board, has dropped by 75% in 21 years!
The cost of becoming an instructor has now risen to the point where its difficult to recover the cost, the cost of moving on to instrument and ME instruction is prohibitive, which means there is no natural route to commercial instruction any more.
With the continued pressure on airfields from developers and the environmental lobby, one wonders if GA will survive the next 21 years!