Burned by the nanny state. Next thing you know they'll require passing a rider's skill course before riding their improved dirt roads.
Being a native son and never having been to Catalina (or any of the other Channel Islands) though, I'm considering heading over there for a day or two. Not that it's challenging, but that it's a unique opportunity to ride on the only Channel Island where it's allowed. Improved dirt roads are an easy climb on MTB gearing and I can easily cover all of the open roads out there in two days, taking time for side-hikes and photo ops.