The signage on these streets is marked as private, so I *think* that private is correct? The implication is that the public should not be allowed and that seems to line up with the wiki definision for access=private:

"Public access is not allowed. Access is granted with individual permission only."

And I don't think that it should be access=destination as the wiki says "Note that "access only for residents" is private."

But to your direct question, there are no barriers or physical mechanisms to prevent access other than signage.