I think the answer is very simple. Regulation. If there was no regulation or very little then anyone could open up an ambulance service and the cheapest costs and the best service would win.

Unfortunately that’s not the case. It’s like day care. Day care is expensive because the government mandates it to be expensive. Otherwise you’d have grandmas down your street would gladly watch your kid but it’s generally not allowed for more than a couple kids.

Same thing with houses. I have half an acre. Could easily put 2 affordable tiny homes on it. Good income for me, cheap rent for someone else, but, unfortunately it’s legally blocked