He didn’t say high COL city, he said high COL country.
Plenty of people retire without engineering salaries in the US. $5k/month after taxes and expenses can be enough (or it can be a fraction of what you need).
Agree that thinking of it as a never ending money tap is the bigger issue.
But yeah if you gave me $10k/month pre-tax today (assuming it was never-ending) I’d be done working for the rest of my life.