Like PS5 games are smaller on average than their PS4 versions

My favorite example of this is Subnautica. The system didn't call on the assets as quickly, or a different way I can't remember all of the details but essentially they had to put like five copies of every asset on the ps4 version to get it to run properly. The ps5 accesses the assets fast enough it only needs one copy. At least that's how it was explained to me.