Why is tech salary growth so much slower than market growth?

FAANG stocks have gone up 4.4X in market value in the last 5 years[1] but average salary for software engineers has only increased 30%[2]. Why is that?

A few possible explanations: - Startup sector is not doing nearly as well as FAANG, dragging down the average - Increase in supply of talent is outpacing market growth - Tech people should be demanding higher comp and are buying the dream too much.

[1]https://www.etftrends.com/advisor-solutions-channel/5k-faang-5-years-ago-worth-today/ [2]Payscale