Some builders are trying to respond. There is a stigma about aging, and there is a perception that a lifetime home looks like some place that you would retire to, with grab bars and other things. I have a very good friend who heads HomesRenewed, the American program on aging in place. He is a carpenter, and he says that the best solution to aging in place is a two-by-four, a hammer, and some nails at the time you are building the bathroom, in the right place. It costs pennies.
It's just that kind of thinking that we don't have.