The median American has a 401k, yes. The median amount of stock owned is, I believe, $40,000 -- so, at the recommended annual withdrawal rate, that puts you at $1,600/year of spending money.
Let's assume that the stock market 10xes in the next decade, then the median American stock owner can get out $16,000/year.
I say this in jest, but at the rate inflation has been going $16k per year might buy you a hamburger in 10 years.