I have not actually read the California statutory provision but it purports to be summarized in the complaint filed by the US. Obviously, California feel strongly about the sale of federal public lands and the conversion of open land in its natural state to developed land. On the other hand, that desire to protect federal land runs not only into the Supremacy and Public Property Clauses of the federal Constitution, but also into various federal statutory provisions relating to the use and sale of federal public lands.
Ideologically, the state desire to protect federal public land against the conversion of at least a portion of the land by the Trump administration represents a basic conflict between two points of view regarding the use of federal public land. Unfortunately, this may be more of a political decision-making process than a legal one: federal constitutional and statutory law would at least seem to have the upper hand here.
It is interesting to read the 1940 case involving the city of San Francisco: US v City and County of San Francisco, authored by one of my favorite Supreme Court Justices, Hugo Black, who noted, after quoting the Public Property Clause:
The power over the public land thus entrusted to Congress is without limitations. And it is not for the courts to say how that trust shall be administered. That is for Congress to determine. Thus, Congress may constitutionally limit the disposition of the public domain to a manner consistent with its views of public policy.In any event, it should be interesting following the arguments of both parties.