And utterly disgusting to see how far removed from reality some people here are. A million dollars is life changing money for the vast majority of the population, and well beyond what most engineers earn.
Let us assume that you earn 16 USD per hour and you work 8 hours a day for 5 days a week, you would earn 33280 USD per year before taxes and deducations. Nowhere near a damn million.
There's also a difference between retirement savings and net worth. I'd guess there was a jump in "house poor" millionaires over the last few years.
The Fed has a Survey of Consumer Finances which can graph net worth broken down by perentile. You're right that even $1M net worth is not the majority, but top 25%ile:
https://www.federalreserve.gov/econres/scfindex.htm?mod=arti...
https://www.federalreserve.gov/econres/scf/dataviz/scf/chart...
Probably more millionaires in the last few years with inflation though.
This is all US-centric; the author, Richard, is in Japan; I'm not sure how net worth, savings, retirement, or taxes are in Japan.