I'm aware that compression rates are a trade-off between space and processing time, and that there's some balance to be had. However, I don't see this balance from plenty commercial games; what I see instead is disregard.
Here's a made up example. Suppose you have a choice between compressing a game:
- to 10 GiB, and it takes 2min to unpack it in a certain machine
- to 3 GiB, and it takes 8min to unpack it in a certain machine
FitGirl will consistently pick the later option. And it would be fine if devs picked the former, or a middle ground... but they don't. Instead, often you get a 10 GiB file that takes 10 min to unpack, the worst of both worlds.
And it isn't just a matter of the compression algorithm. The developers also have the freedom to choose how they split files; but they often create 9001 files the size of an ant, that is going to hurt decompression times. (Paradox Interactive, I'm looking at you.)
Tagging @fiestorra@discuss.tchncs.de, as it addresses what they said too.