Because programming is concerned with "details", it was considered clerical work from the beginning. Look at the indignities suffered by Jean Bartik and the female staff that were assigned to program ENIAC. Do you think they would have assigned women at the time if they had any idea of the intellectual challenge of programming?

Since programming is considered low level work, it's always been a smart move for programmers to find their way out of it into management or whatever. Relying on the good will of employers has always been a dubious proposition (except maybe during the American post-war boom—a unique period in world history), so it stands to reason that most programmers would be looking to move up and out.

In most professions that have similar age barriers to early exit (sports comes to mind immediately) one case expect to be compensated handsomely for the short while that one has is holding on to the position, this is not the case with programming.

In the case of sports you have 10,000 people that aspire to every single paid position. If programming were that way, where vast swaths of people practiced daily from age 6-21 in the hope of snagging one of the glorious few spots, then you could expect pay to scale accordingly. As it is, I think the economics of being a startup founder are a bit closer to professional athlete.