>One is because homes today are substantially larger and have more amenities than they did in previous generations.
I have noticed that most of my fellow millennials seem to have completely forgotten the concept of "starter home" and assume that as soon as you turn 25 you should be entitled to a 4 bedroom house with a pool, huge yard, wonderful neighborhood, three-car garage, etc.
Among my friends that have bought houses, many of them have gone into significant debt just to buy a 3-4 bedroom house, even though they have no kids and only use one of the bedrooms, because they think that at some point in their life they will put them to use. The extra rooms go completely unused (other than the extra furniture which they also went into debt for). It's like they see the house that their parents own and assume that their house also needs to be that, and ignore the fact that their parents probably started out in a much smaller home and then moved into a big one once necessary.
>Two is that we're highly skewed to a handful of elite metros
I contend that it's not even just this, but also that within metros millenials are highly skewed to a handful of elite neighborhoods.
I live in a medium COL metro, and all of my friends constantly lament the "high" cost of houses and how they will never be able to afford a house. But when I ask what houses they are looking at, it's always the nicest, premiere neighborhoods that have McMansions with huge yards, white picket fences, hip restaurants within walking distance, etc. Not a single one of them even considers living in the many much cheaper neighborhoods.
There certainly are issues with prices in some areas (cough SF cough) but at least in my metro and in my friend group, the "houses cost too much" meme seems to be a scapegoat for what is really just an inflated sense of what housing they are entitled to.