Google brought me here looking for answers. I am also missing the sunroof vent feature. I am on 2017.46.8 50d6145. It installed a couple of days ago. The feature was there a few weeks ago before the update. I used it frequently. Now it’s gone.
Based on the info from this thread, it’s looking like people who got 46.8 lost the remote sunroof vent functionality.
I recall reading that one of the changes in 46.8 (or maybe the prior version) was a security fix to deal with car thieves who could spoof a key fob and unlock the car. I didn’t see that listed in the release notes, but read about it on Teslarati. Maybe that change removed the remote sunroof venting function, either intentionally or accidentally.