kids to come visit.
So basically, they keep the larger home purely because they want extra bedrooms that get used a couple times a year.
In fairness, if you home is paid off, who really cares at that point. But I see a few people still struggling to make house payments on large homes with only 2 people in it. In that case, they would greatly benefit from downsizing and pocketing the cost difference.
On the other side my wife and have actually talked about in a dream world we would get a large house in retirement so everybody could come visit at the same time.