The issue is that in ED every single thing is huge, there are barely any small objects in the whole game, so it's very hard to get a sense of scale in 2D.
In all the other game's mentioned in this thread there is a healthy mix between object sizes, from tiny to huge. In ED there are very few visible objects overall and nearly all of the existing ones are enormous, so without VR it's pretty much impossible to grasp the actual size of things. Ships are huge, stations are huge, station buildings are huge, hangars are huge, planetary starports and it's buildings are huge, planetary landscapes are a mix of completely empty huge plains and huge montains and craters, nothing really stands out, there are no references to get the idea of size. If everything is huge, then nothing is huge.
For instance, when flying to land on a planetary starport, when you feel like you're nearly there you're actually around 10km from the ground, which is roughly the cruising altitude of a commercial airline. But there is no weather, no clouds so you don't even realize how high you are. Plus, the only thing visible is that gargantuan mammoth sized starport, with only empty land around it, with 2km high towers. So you feel like you almost at the ground even though you're still at a very high altitude, several km away from it. Due to all that you can see being bloody enormous, then nothing feels big or afar. And there isn't a single thing in sight, no traffic, no small buildings, no people, no moving small vehicles, that might help you realize the actual size of those things.
This is also the reason why ED ships seem so slow, the near complete lack of small objects (and overall lack of objects), it feels like you're barely going forward.