These homes are priced in the millions and are generally not in areas known for high salaries. Coming up with that much money is out of reach for most members of younger generations. Some people may be interested in buying these gargantuan homes, but they can't afford it.
And as the article states, the generation that can most afford these homes, boomers, is losing interest in these homes because they are coming to terms with how impractical they are as they age.