What is supplied is different from what is in demand. No one wants to build small homes on small lots that don't add up to big money. A few years back in Bton a couple dozen Habitat Houses were built in a short time in a small area in an "undesirable" part of town. I haven't driven through there in some time, but shortly after it was done it was a great little neighborhood full of you families with kids playing in the yards and riding their trikes and bikes in the street, straight out of Ozzie and Harriet. These aren't rentals, they're owner occupied and affordable for working class folks. These are the kind of things that need to be done at scale.
Edit to add link -- hope this works:
Find local businesses, view maps and get driving directions in Google Maps.
www.google.com