For me this has to be looked at from the point of who it affects the most. A person that already has a house is much better suited to "take the hit" of property prices than someone that doesn't have one (in general terms). Obviously you have to manage it, but in the end you should strive to protect those that are more vulnerable.
People least likely to be positively affected by a house price crash include people that don't have houses, the majority of whom face considerably more difficulty and up-front expense in obtaining a mortgage in an environment of falling or unstable property prices.
Sure, there are some beneficiaries from a house price crash, just like some people make money shorting a failing company. That doesn't mean there isn't a deadweight loss, and if your conception of people who are "most vulnerable" to property prices prioritizes the welfare of those with no significant exposure to property but plenty of liquid funds and a long term investment horizon, it's a very strange conception.
Much of the world is still suffering from the after-effects of a major house price crash in the US several years later; I'm genuinely quite saddened that some people are so adamant the effects of that must have been "zero sum" they feel obliged to reach for the downvote button when HN commenters have the temerity to suggest otherwise.