“McMansion” is just a way for The System to shame the middle class for daring to want some space to live in, and I'm disappointed when I see anyone propagate it.
Better than "McMansion" even is "Faux Chateaux"
(Having a big spacious home is not something I'd safely criticize as I have 6 acres and a house a bit too big for the family. The simultaneously ostentatious and ... ugly... yeah)
It also makes the house fit on a smaller lot if the driveway is straight to the road.
Most if not all McMansions are builder's specials designed to be sold and upsold; often if you go to the builder's site you discover that the lowest end version of it actually looks pretty sane, all things considered.
You misunderstand; the target audience for ”McMansion Hell” is not the people living in a ”McMansion” but those who have less than that and would aspire to more.