Bumping this because I have the same issue.
FB post was asking about this. Claimed pass side 2nd row vent was working, on max AC, but nothing on the driver's side 2nd row. Lots of folks claim to have the same issue and when brought in for service, the dealer told them "normal".
So i hop in my '23 and low and behold, same thing. Very little to nothing out of the passenger side on max AC.
Is this really "normal" or should I make an appt?