We already have tens of millions of homes made for multigenerational housing. We call them McMansions
Yup! The boomers were raised in 1,000 sf one bath homes and now live in 2,400sf three bath homes that can support three generations.
Don't point that out to them, least they start squealing about how they NEED their room and the younger generations, if they just applied themselves; could surely take advantage of the silver platter economics boomers had enjoyed in their youth.