It's essentially saying 'It was an honor to meet him;' that could mean that you were undeserving, or simply that it was something unusual that most people didn't get to do; if it were common, it wouldn't be a privilege, would it?
In the thread's context, usually it's associated with not granting the privilege to someone else, as well - you have a privilege that others do not, one that you do not do anything to deserve.
I don't know about you, but I don't really believe that 'white privilege' is intended as a positive. It's intended to have a negative connotation, otherwise there would be no impetus for change.
I also agree that terms like "white privilege" are intended as criticism. However I don't see them as criticism of the individual who has the privilege, but rather of the society whose circumstances gave them that privilege. The term is an attempt to promote systems thinking.
