Another friend did make the jump, mostly for the money and career opportunities and she's struggling and feeling a bit demotivated. The CS theory is quite hard, and it's not something she's especially interested in.
These anecdotes don't prove anything, but I've been thinking for a while if the mental toll of this profession is really worth it.
We say that the others didn't make it into the industry, but what if the others are clever enough to avoid having to spend all day in front of a computer working on very abstract things that aren't really understood by most of the people in their lives, including their managers and a significant number of their colleagues.
Having to spend their free time studying just to keep up with the latest fashion, doing overtime, going through the interview gauntlet every damn time, getting shafted by incompetent business leaders and managers.
Programmers are kind of the punching bag of the software industry.