Isn’t a full HD resolution ( 1920 x 1080 ) almost four times less pixels than 4K ( 3840 x 2160 )? I think I understand that a higher bit depth gives me more information per pixel, resulting in for instance less banding, but I still expected my 1080p 10-bit video files to look very soft and literally low-res.
Also 1080p 10-bit probably has good encoding. DVD content probably not-so-much, particularly in the era when it was expected to be viewed on CRT screens where some softness was intended (in other words, the same thing that happened with pre-HDMI consoles and flat panel displays).