Some of them makes sense. Others do not. Some of them clearly block us from seeing unfinished areas. From the building in the Steppes you can see a big gap where the Divide and the Wall are supposed to be. Stuff like that. So it makes sense from the point of view of a developer, but doesn't really help me as a player. Others just make no sense at all. There are a few building levels in Mars that you should totally be able to get on, there's absolutely no way that they could show you unfinished areas or disrupt gameplay, but they're blocked anyways. The area on Mars before you go down into the train station, I can never remember what it's called. You can sneak up onto that central rooftop, which is much higher than some of the other platforms, but almost every single other rooftop area is blocked off. It's just weird. You have a game with awesome jump abilities that should help you explore, and a good chunk of the levels have invisible walls that totally discourage it. Destiny 2 needs to have more of a vertical aspect to it. So many opportunities for hidden places and jumping puzzles.