"What the public wants" is relevant insofar as it allows the legislature to craft law within the space of what is otherwise legal. (Here, for example, if the "public wants" beach access, California may pass a law raising money to buy an easement over Khosla's land.) But public whim, or even public whim translated into state law, cannot overcome property rights and federal treaty obligations.
So I understand the lawyerly arguments here. You've done a great job explaining them.
Here in California we do hold what citizens want to a great degree of value. We've worked for a more direct democracy with citizen initiated constitutional amendments and more recently, citizen initiated redistricting.
With this in mind, you have to concede that at some point you're going to have a harder time arguing lawyerly points to an ever-growing statewide coalition.
