People often vote against their self interests. It is especialy easy to "baffle with bullshit" when it comes to the housing market.
We see this happening with scientific discourse and political discourse across the world. People just want a simple answer and science/politics/finance cant give it to them, because it always "depends", so they defer to the people with the simple answers ( liers ).
A person is smart, we the people are pants on head retarded.
So to answer why people want their house to go up in value even though it is detrimental to society, because "Your worth just increased by $100K" is a simpler answer than "Yes your largest asset increased in value but you still need a house so if you sell you still need to buy a house that has increasd by the same amount in the same time"