The reason is because it is a terrible job. Unlikely 90% of other jobs, you have to mentally burn your brain out each day, constantly learn new things, and focus intensely, supposedly for 8 hours. The reward is nothing, not even good pay outside of a couple of tech giants in the USA. If you compare it to a trade, there is a night and day difference to your mental health.

The wage data in this article is meaningless because it ignores the fact that the few places with the 100k+ wages are all in ridiculously expensive cities. Those wages bring up the "average", making it seem high.

No sane person dreams of sitting at a computer all day doing harder things than everybody else sitting at the computer and making average pay. Not only that, but most employers would rather pay a person $5 an hour to make their app from somewhere in yemin then they would hire a local person.

You also never get to be part of any kind of inner circle within the company. You will be paid less than some random useless person who "knows somebody high up" and is in charge of "managing" you.