There’s a bus service, but historically, there have been some very nimby reasons for why there’s no faster transit in and out of this region of the Bay Area.

TL;DR: having access to a light rail train would have meant less drivers paying tolls and the board owning the Golden Gate Bridge would want that.

For more about this in SFGate. I know this doesn’t make the journey from Richmond to San Rafael shorter, but BART has been known to expand their services and it’d probably still be faster going around than waiting in a car.