Earlier quoted context omitted.
If density increases the people who will benefit the most are current landowners. If you have single family home on a big lot, its value will go up many times if you can suddenly build an apartment building on it.
That's not the way it works. The reality is that the apartment building goes up and you house is worth nothing unless the government allows an eminent domain for your property or a developer with the bucks to buy out the neighborhood shows up. Until that happens, your house lost a third of its value because there's an apartment next door. If you're unlucky, rates go up and you're stuck.
Is it really controversial to say that a regular single family house in a single family house neighborhood will go down in value when somebody decides to plant an apartment complex right next to do?