Actually, the opening sentence is wrong.
..."Supply and demand: thats how the market works, more or less, when regulation doesnt come into play."
It still works, especially when regulation is in play. That's their problem.
And I am not against "regulation"; regulation is necessary for us to function efficiently and harmoniously as a society.
But you can't have development or density restrictions without a market reaction, which in this case is high rent.
And if infrastructure is inadequate to handle these units, perhaps the city need to re-price how they deliver such services, which might possibly make these units economically nonviable.