Yep, even high quality 24-bit uncompressed imagery often benefits from dithering, especially if it's synthetically generated and, even if it's natural imagery,

Yep, even high quality 24-bit uncompressed imagery often benefits from dithering, especially if it's synthetically generated and, even if it's natural imagery, if it's processed or manipulated - even mildly - it'll probably benefit from dithering. If it's a digital photograph, it was probably already dithered during the de-bayering process.