AOTC was filmed at 1.4K, not 2K… or at least much of it was. The HDCAM tapes could only record 1080p at 3:1:1 subsampling which is a luma resolution of 1440x1080 (which was cropped to 1440x818), and a chroma resolution of 480x270. It was also only 8bit, so not a lot of dynamic range to play with. I believe they had to hand-draw the mattes on many greenscreen effects. Not all of the film is that quality though, sometimes they would have reduced the size of the live action which means that it may as well be 4K (luma anyway), and sometimes they may not have used the HDCAM and instead recorded using a different data recorder capable of 4:2:2 sub-sampling, but it’s unclear how much was actually recorded at that rate. In any case you can see from the film many scenes where the chroma resolution is quite low - doesn’t always matter because they don’t have sharp contrasting colours on the live action, but I can make some examples of that sometime.