or even opening a website that uses less than 10mb on initial load

yep it was… which makes it more impressive to implement it this way

The randomized empty open world planets wasn’t great but they also did that in Daggerfall so I don’t think it was totally unprecedented

Well, in case of daggerfall you could actually move through the land to the next city/town without a single loading screen. And in theory you could move from one end of the land to the other end (but the game would likely crash due to procedural generation or memory issues before)