surveys in my country repeatedly show that renters would prefer to own.

That does not mean they prefer to own right now. If you plan on moving to a new place in a few months, for example, it would kind of silly to buy only to have to buy again a few months later. You may prefer to buy, but the rational person would rent for a few months to bridge the gap, and then buy once they get to where they plan to stay.

And, given the current state of housing, with a high risk of it soon imploding, a lot of people would rather wait a few months, even a few years, before they buy to see what happens to the market. Again, preferring to own doesn't imply right now.

The data shows a clear downward trend in price, especially in the traditionally desirable areas. If you have somewhere to rent, why would you choose to buy at this exact moment, knowing – with reasonable confidence – that a house will be cheaper in six months?