the only alternatives for trying to deliver some of that using less data, such as No Man’s Sky and their heavy use of generation, end up with results that quickly feel repetitive

This is an area where generative AI can actually really push the envelope and be completely gamechanging. It’ll require a ton of work for it to get it right 99.9% of the time without outside input, but it’s going to be really cool when game developers do figure it out.