This likely gives them confidence that if they were to remaster for a different color-space or higher resolution, that they could. For a 4K original shot in 8K, Netflix could send it back through the production process for a more reasonable cost and be able to launch the title quickly.
I'm surprised they don't ask for VFX sources to be archived though. ST:TNG and Babylon 5 both suffered badly from loss of the original VFX.
I'm surprised they don't ask for VFX sources to be archived though. ST:TNG and Babylon 5 both suffered badly from loss of the original VFX.