Saying "They take hundreds of gigs because they don't use ANY compression." is absurd when you immediately have to caveat that codecs like BC7 are used for texture data, which makes up a large portion of the shipped data.

Sony included dedicated compression support in the PS5, licensed from a leading middleware company, specifically to make it easier to use compression in games. Games are using it.

I don't know why you're trotting out this misinformed BS.

You can also simply watch the statistics when Steam is installing a game - the amount written to disk is larger than the amount downloaded over the network, because they also compress assets in flight to reduce bandwidth usage (the most important thing, since raw assets often load faster from an SSD as long as you have available storage.)

You can argue every single file should be compressed at rest on persistent storage after install, but that's a losing argument. People really hate longer load times, so compression at rest is only appropriate if it improves them.