I don't think Git itself is a revolution or new technology. It took what people were trying to do (but with extremely frustrating bad user experience, like taking an hour to change branches locally) and just did it very well by focusing on what is important and throwing away what isn't. It's an achievement of fitting a solution to a problem .

I don't think they DID build a modern computing environment at all. They built something that kindof aped one, but unlike Git they missed the parts that made a computing environment useful for users. It's more like one of those demo-scene demos where you say "Wow how did they get a commodore 64 to do that!?"

If they did build a modern computing environment with 20k LOC, that is a trillion dollar technology. Imagine how much faster Microsoft or Apple would be able to introduce features and build new products if they could do the same work with 2 orders of magnitude less code! That is strong evidence that this wasn't actually the result.