So my theory is that GTA 6 is somewhat larger and they really didn't want to invest into engineering a solution for multiple-disc or something when ~everyone downloads their games nowadays anyways. So in some sense, the true physical release "can't" exist.
This doesn't apply to most anything but GTA 6 is the one example I think could very realistically be unable to be stored on a disc at all, or unable to be stored on a 3-layer and the supply chain just isn't there for 4-layers in 2026.