Yes - you are correct - I was thinking about ships other than Princess. I usually check on most ships because my laptop has an HDMI output. I was able to jack in on Norwegian Epic - but that's the last time.
I am pretty sure I checked on Royal Princess and did not see one available, not easily accessible and any case. The TV does not move much because it is already situated in a good viewing area.
I am the editor, but I also speculate, ask questions and play devil's advocate. I reserve the right to change my mind.