While I am not thrilled at this change, as I use the UC a couple times a year when flying OALs, I will say I've been very pleasantly surprised that what sounded like a really silly restriction on Amex Centurion lounge access (must have BP for flight departing w/in three hours) has resulted in a truly drastic reduction in lounge crowding at SFO.
The lesson would seem to be there are more people taking advantage of generous lounge access rules than we might think.