Some people do accumulate capital in their houses and downsize. But even in cases where it happens, they might have been better of with cheaper housing costs all their lives enabling savings amounting to more capital at retirement.
Homeowners might end up on either side of this equation. Rapid growth periods place earlier buyers in a better relative place to later buyers. But I think the upside is over valued by home owners while the downside is undervalued. Much of the upside is in fact access to capital.
It's interesting how foreign the idea that lower prices make us wealthier is when it comes to housing.