It's been interesting to see the different financial perspectives on the threads here. I don't know if people haven't done the math or just think a middle-class lifestyle is supposed to be living in mortal terror of an unexpected bill or expense.
I personally think of it as an aspirational descriptor, maybe on par with the lifestyle a single union-employed factory laborer could have afforded many decades prior. I don't care if that now requires a 90% income. We're a wealthy country, that's reasonable. If living in the 50th percentile is a fraught subsistence wage...that's a problem!
My guess is $220K for a family of four if you don't already own a house is not excessive at all. Housing is bonkers. Owning the real estate free and clear would make a big difference, but if I "only" had $220K to retire on and had to pay my rent, I'd move somewhere cheaper and I like it here.