"Only" 20GB. Is that sarcastic, or is that actually low for a videogame these days?
Games have gotten insanely huge.
100GB is more or less expected for big name games nowadays
Consumers' computers have more space. There was always a trade off between optimizing for disk space and all the other things that go into making a game. As demand for the former has fallen, developers responded accordingly.
Also for performance reasons most games are shipped with uncompressed lossless assets which adds up to become huge.
2 TB SSDs became affordable ~5 years ago, and HDDs of similar size were affordable long before that. Unless you have a laptop from a manufacturer with a pricing model designed to create artificial scarcity of storage space, 100-gigabyte games are not a real issue.
When disk space isn’t a problem and with loading times being already rather fast (other than any shader pre-compilations that are CPU bound) there is no penalty to large games.
Not only that but having very large games can be sort of a moat especially on consoles, if you can only have 3 games until your drive gets full you might think twice before uninstalling call of duty to try something new.
And whilst this can also present a barrier to entry the big IPs have enough initial pull to overcome any downsides most likely.
I still think of a megabyte as a lot of memory at some level because it is and that was enough to run approximately every DOS game including the first Civilization...the new one requires a minimum of 16GB RAM, so about the same rate of growth in requirements.
The ram requirement has doubled from 8 to 16 GB though