I'm not too familiar with the causes of the rising cost of housing. Is it right to assume that lack of supply is the main factor? If so, what should US/CA be d

I'm not too familiar with the causes of the rising cost of housing. Is it right to assume that lack of supply is the main factor? If so, what should US/CA be doing to address this? What are they currently doing now that makes the problem worse? Looking for a better source than the article above which feels a bit fluffy.