Reference? Are you implying that developers over 55 are unemployed against their choice?

I suspect sampling bias: Any half competent 55 year old has lived through some golden opportunities to make bank, or decide on a career change by choice. Also the intake cohorts results in not many over 55 as a % of total. My experience in New Zealand is that older devs are doing fine as a cohort, although I also can see poor performers who stuck with old tech who may have bitter anecdotes.

> You need to own the economic value of your output as early as possible

I disagree. I have plenty of 50+ acquaintances doing very nicely on their boring salary without the stress or risk of trying to get a slice of equity. Plenty of people do not have the traits required, or their personal circumstances are not flexible enough to allow for risk, or they just want a 9 to 5 and a comfortable retirement (which they will get, and their rockstar friend might not).

Edit: Past performance is no guarantee of future results. The outcomes for the first cohort of developers is very unlikely to be anything like the latest cohort who you are advising - “as early as possible” doesn’t apply to 55+ year old developers?! We haven’t had 30 years of hindsight bias to know what the successful path for a current 20 year old will be.