There was an article I read recently about this fight where Khosla said he's now continuing the legal battle simply on principle. He doesn't actually care (that much) about public access any more.
He didn't buy the beach, you can't own beach in CA afterall, but the beach truly is inaccessible by any means other than through the private property which he does own. The previous owners of the property allowed people to enter the private property on their way to the public property, and had done so for so long that people have never had to think about it, but the new owner doesn't feel he is obligated to do that, so the loss shocked a lot of people who have been using the private access road. Their supporters feel that because the previous owners allowed it, that the future owner should be obligated in some way to allow it as well. Khosla disagrees.
And Khosla's dispute isn't just about access. He also wants to stop running the for-pay parking lot and restrict access to the sandy beach above the high tide line (which marks the border of his property with public land). His argument seems quite strong on these latter two points imho.
And since it is his property, he should be able to close the parking lots, bathrooms, and general store too, especially if he were to be liable for maintenence, upkeep, accident liability, etc?
While at first glance that may seem unlawful, it has been thoroughly tested in the Courts. This is not an unusual occurrence; everywhere along the California coast you will find land and businesses who provide coastal access as a routine matter.
I assume Khosla has competent legal counsel who would have told him all this before he bought the property.