On cars I agree wholeheartedly. It’s way too expensive to maintain that capacity. We rent a minivan to travel but buy small car for daily use.
House I am not convinced, the value proposition is different. It really is nice to have a little extra space. Not some monstrous McMansion, but not cozy, and space for the kids to have their gaming computer stuff not inside their bedroom and my home office stuff not inside my bedroom. And moving is a pain in the ass and expensive, absolutely don’t want to have to scale up if the family gets bigger.