roadway leading up to and the bridge itself has been changed to access=private but really you can drive on it then turn around once on the island before the gatehouse so I think perhaps access for these roads leading to the gatehouse should not have private access, at a minimum maybe permissive? But it seems that this changeset https://www.openstreetmap.org/changeset/142310136 updated it to private based on that the ownership is private which is not the correct use of the access tag.