Sadly, I had the final cinematic (patch 11.0.2.56461) ruined by the UI showing over the top. I attempted pressing Alt+Z to hide the UI but that did not work.
Unfortunately, the screenshot I took did not seem to save. From memory it was mainly all of the Action Bars that were still showing, as well as the Pet Frame, and a couple of smaller things that I cannot recall. The Minimap, was definitely not showing, and I think the Objective Tracker, Chat Frame and Buff Frames were also hidden. It appeared to be loading in not already downloaded content at the time, as there was a rotating red then green circle at the top. Perhaps that always happens, but is hidden usually?
I did have the following addons active:
Adapt
DialogueUI
DynamicCam
LoreKeeper
Macro Toolkit
Narcissus
Plumber
I thought it was worth reporting, in case it was not already known. I understand that there were previously audio issues with the same cinematic. In any case, hopefully it is a bug that can be squashed.