From their study, they also use the 40th percentile of rent, which manipulates their results to their favor as well.
Also, roommates are a thing. It's absurd to suggest that everyone, even minimum wage workers, should be entitled to their own private kitchen, bathroom, and living room, let alone an extra bedroom on top of it. Americans rank among the highest in living space per Capita, so we spend emit a lot of CO2 heating and cooling spaces that we're not even inside.