Conservative voters tend to be older, own a home purchased years ago, have a lot of their net worth and personal retirement funds tied up in its increased value, and worked a long time for a private pension which has a lot of investments in property. It would need an 80-90% drop in house prices round here to return to even the levels of 1995, and if you told your main voting block that was your plan - reduce a big chunk of their net worth and pension funds by that much - they wouldn't vote for you anymore. Plus you'd have a less estate taxes coming in, and a lot more homeless pensionless elderly people for the state to take care of. And if you told people who paid into the system all their lives that you were doing it to help young people who have (comparatively) paid in much less and (popular media perception) have it easier, are more entitled and lazier, that also doesn't go down well.

> "when the real cause is well-understood"

I don't know what you are thinking there, but a lot of people suggest "not enough homes" is the real cause and "build more homes" is a solution; but most people in the UK live in a home, there aren't very many homeless, and there's not much benefit in having so many houses beyond a bit of slack in the system, building tons more of them just to sit empty year on year would be a waste. The real cause is not a single cause - the homes people live in tend to be owned by landlords instead of themselves, cheap credit means people can borrow more to buy houses so they can outbid others, pushing others to borrow more in response, pushing all prices up. The rise of buy-to-let mortgages helping people afford more houses now than they could in the past, increasing competition and pushing up prices that way. Inflation and the devaluing of the £, if the value halves in real terms then a £50k house becomes a £100k house and appears more expensive. Pension funds and private investments allowed in the housing market where commercial groups can throw around a lot more money than individual buyers and pay more for the more desirable properties. Competition among estate agents incentivised to present houses as worth more to get more commission; council tax, rates, and some taxes being adjusted based on house value/size/location and cheap credit meaning people can borrow to have a kitchen redone or an extension built - many small incentives like that for different groups to increase the value or argue that the value is higher than (some previous level) for their benefit. The ability for wealthy foreigners to buy property in the UK which they don't intend to live in, but want to use as some kind of diversified asset portfolio or laundering (e.g. a house valued in Pounds Sterling, instead of a bank account valued in Rubles or Renminbi) rather than the government acting to keep houses for habitation and nothing else, the rise of personal cars in the last fifty years meaning people can commute long distances into London so they are willing to pay more for a house in a village than anyone who wants to live and work in the village can afford...

There's all kinds of causes and influences; there's only two ways out that I can see - either a sweeping change to houses for habitation only not investment or landlording or anything, which will collapse a lot of people's wealth and be extremely unpopular, or a devaluing of currency until a half million pound house is something anyone can afford because that's not much money anymore.