You mean other than that it’s a terrible usage of land in a region infamous for having extreme demand for housing?
America is a country of laws. If there is a desire to make policy changes, then it has to be done with the consent of the governed. The majority in Atherton does not and likely will not consent to such things, and Andreessen registering his discontent is just a citizen exercising his legitimate rights.
Yes, the fundamental political argument here is whether “setting up a town such that some small group gets to decide what kinds of buildings a property owner can build” should be a thing. There are clearly other premises that nearly everyone agrees cannot be enforced by a town (say, “a town set up for white people only”), so it’s not good enough to simply provide a premise and say “we’re a country of laws therefore the premise shall be enforced.”
The real culprit is not Andreessen complaining to his mayor, but the Bay Area and California politicians who have squandered the enormous revenues of the past 10 years and have literally nothing to show for their housing efforts.