There are lots of people out there who like it when their house goes up in value. Of course, you can only benefit from that money if you sell up and go live in a one bed flat somewhere, or after you die your kids can all go on luxury holidays. But there is a down side.
If you insist on having a housing market where houses are priced according to what people can afford to pay, not according to what they cost to build, then people will get burnt every time there is a real financial squeeze. Who knows if we will get one now, but we will get them.
Only way out is to increase the supply of houses so they become more affordable. Then when there is a financial squeeze people will have a lot more slack and there will not be any sudden market collapse.