Around where I live, a millionaire is a 65-year-old retired schoolteacher with a perfectly normal suburban house they own outright after a 30-year-mortgage and the minimum retirement savings recommended to be secure. I'm not convinced you're ethically obligated to not have a house or retirement savings. (In fact, I would prefer if everybody had a house and enough retirement savings.)

That said, this person could buy a perfectly normal suburban house in cash anywhere in the country and then sock away enough in retirement savings in less than two years and then go become a public school teacher, so I don't think that applies to them.