Better yet, build something worthwhile on the space. Housing, shops, transit - there are clearly going to be a lot of people going here on a regular basis, why make it so that they have to live far away? The rooftops of all of these places can then host solar panels, without actually wasting the space below them on something as useless as car storage.
For a while, Facebook was going to be putting some money into rebuilding the Dumbarton Rail Bridge and having a stop at its campus (pictured) on a route between Redwood City and Hayward, but with remote work and interest rates being what they are now it seems unlikely it'll ever go anywhere.