Here's the brief sequence I was talking about in the other thread. It looks like this was simply upscaled from SD, doesn't it? It's even more jarring in motion, actually.
Good catch! I can now see what you were talking about... those are scaling artifacts. For some reason the original shot (after being scanned from film) ended up with a vertical resolution of 540p, and they did a simple "Nearest Neighbor" enlargement to 1080p.
You can verify this by taking the TrekCore image into Photoshop and reducing the vertical resolution by half to 540 (uncheck "Constrain Proportions"). The image will now be squashed, but the "jaggies" will be gone. Now scale it back up to 1080 using "Nearest Neighbor"-- it will look the same as it did before.