If one gets married, why wouldn't the spouse inherit everything, unless each party made special provisions. If this man wanted to leave his estate to someone other than his spouse, he should have done so. By the way, I don't think the Courts involved here were in California. (Certainly not the Supreme Court)
In many jurisdictions the surviving spouse gets half and the children of the decedent get the other half, if there is no will. Or, if a will is executed before marriage, the marriage supercedes the will and this rule is implemented.