Shooting the messenger has a bad record for making things better. Speculators don't drive markets, they just signal how the situation will develop as early as it is possible for predictions to be made.
Cracking down on speculators won't help people get roofs over their heads. Nor will calling them unethical. Speculators are the signal for whether there is going to be a housing problem in a few years time.
We should want a system that allows speculators and encourages them if there is going to be a housing problem so there is plenty of warning. Targeting speculators in particular is the old once-a-metric-becomes-the-target-it-becomes-a-bad-metric problem in a new guise.
This works for most goods that people have to constantly buy new, but does not work in the housing market. The people that decide the zoning are the residents of the city. The residents of the city don't need to buy, so they don't care about the speculation price effect. In actuality, through price increases of the speculation, they are better off! So they vote for SFH zoning[0]. The warning is ignored.
If you introduce a land value tax equal to the value of the unimproved land, this will kill speculation, but also make it instantly impactful to the citizens that there is not enough supply. This will mean that the people able to change the zoning of the city will instantly see a reason to change the zoning, as better zoning means more supply means lower taxes.
In my opinion you're overlooking that a speculator could "engineer" a situation faster than say a local council is able to act / realize what is happening.
For example, a speculator moves into a nice small village, sees potential and brings in a lot of foreign capital in a short amount of time. Buying up houses and outbidding potential new citizens. The price of land is also driven up from this, even if it's only a short term thing.
The damage has been done there and it had little to do with the number of houses. It was just a hostile takeover of a community.
If the speculators are wrong the price goes down and people tend not to complain about them. People only start bringing up speculators when they are correct.
They were right. The speculators from 2010-2020 were right that cryptocurrencies are going to be a reality from now on. Like it or not, it is clear that there is a market here that is measured in billions of dollars and it is going to stay with us.
Cracking down on speculators won't help people get roofs over their heads. Nor will calling them unethical. Speculators are the signal for whether there is going to be a housing problem in a few years time.
We should want a system that allows speculators and encourages them if there is going to be a housing problem so there is plenty of warning. Targeting speculators in particular is the old once-a-metric-becomes-the-target-it-becomes-a-bad-metric problem in a new guise.