I'm the oldest of 9, and assure you we didn't live in a 10 bedroom house.
Couples don't "Need" a bedroom for each child. They don't "Need" 2 new cars. They don't "Need" many of the toys, electronics, vacations, that they've deemed essential.
I think I’m pretty aware of wants vs. needs. We went for years with just one vehicle, never took a vacation, certainly didn’t head south in the winter (still don’t), and my kids were raised the same way.
Yes, some millenials do feel entitled, they feel they have to start off where their parents ended up. Sadly, many of the parents have not prepared the next generation either emotionally or morally.
My generation did a LOT of spoiling kids. It left them thinking they had a cake-walk. They don’t.
I think it’s the lack of proper teaching, the garbage they’re filled with in schools, and the deliberate out-of-reach real estate that is/was stacked against them.