Those coast lines are most likely either inaccessible due to environmental protection concerns, or just straight up not easily accessible — lots of cliffs on the West Coast.

Or just not very fun to be on. The beach cities of Southern California are blessed with having some of the most accessible beaches.

All of the California coastline is public.

California coast is public up to mean high tide. This is appreciably different from, for example, Oregon where it is public further in (typically to the vegetation line, details are slightly complex). It makes it significantly easier for California property owners to de facto remove public access to beaches, which is very common in some areas. On top of this, CA courts have often been reluctant to enforce public rights to beaches.

> Are property rights freedom-preserving?

You’ll find that historically speaking “freedom” and “property rights” are treated as synonymous for some political theorists, including the ones that founded the United States. This is one of the foundational aspects[0] of liberalism that has come to rule the western world; the idea that property rights are sacred and must have an exceptionally high bar for the collective to intercede on.

Whether or not that equivalence is true is a debatable matter. One of the unfortunate outcomes is the ability for the individual to withdraw their property from public use, often to the detriment of the whole (such as the beach example you provided).

Also, the fact that the founding thinkers of liberalism and America itself tended to own slaves or trade in them doesn’t necessarily disprove the basic argument, but it’s a pretty strong counter point at least.

0 - There are of course other tenants to liberalism that I’ve not included here, due to their irrelevance for the subject at hand.