These threads are nothing but speculation some of which has a sound theoretic basis.
Land is typically about 30% of the cost of a house across the country California included.
And there is little doubt that this plan would have a devastating impact upon construction and everything else which is dependent upon financing. Your attempt to refute my comment totally ignores that point.
While your point about avoiding the full impact by building ones own home is valid it is not practical for the vast majority who cannot do that. And living in the house for a while would allow you to escape one of the most absurd features of the FT since you could sell it as used without the crushing sales tax. But most people would get creamed by this feature.
BTW it is the opinions of economists which are used by advocates to push this plan.