Image size is already downscaled to 450 * 380, and afaik most ML libraries downscale the input by default. In that context a higher camera resolutions only real

Image size is already downscaled to 450 * 380, and afaik most ML libraries downscale the input by default. In that context a higher camera resolutions only really affect noise levels due to the effective super-sampling, not the performance of the library (assuming downscaling is an insignificant relative to the hand detection part).