Not to belabor the point, but I suspect that what concerns V22 Osprey is not "how much stuff exists to be explored," but rather "how big is the window onto the world?"
That's an interesting view of it (along with what else you said), but that's not what I understood at all (as you saw). It's an interesting point, but I will say that the window to the world is identically-sized as before. And if you want a larger window, you can actually play with a larger screen resolution, if we're being literal about this. I just switched to a larger monitor size of 1920x1080 up from 1280x720, and I can tell you two things for sure:
1. I can see a ridiculous amount of the game (see the last trailer).
2. The game is running at a great framerate in the side view, but in the old top-down view it would have been chugging performance-wise because of having to draw so much grass.
I'll also mention that the decision to go side view isn't "pretty much set," it was pretty close to set in stone a month and a half ago. Not to belabor that point or be rude, either, but it's important to note I think. We just aren't capable of making the game in a way that we feel that is attractive and fun from a top-down view at this point in time, and the side view is coming along absolutely swimmingly. I'm not really addressing you with this note, Flatfingers, but there do seem to be some folks (not here, mostly elsewhere) that think they can convince us to go top-down again. That's just not in the cards, because with the staff we currently have, and the technology we're using, etc, that game simply isn't one we can make in a way that lives up to the quality standards we are looking for.
Anyway, I very much understand where the fear is coming from for those players who have only ever played games of this sort that are top-down (or those who have bad memories of, say, Zelda 2). Or those that think any game that uses this perspective in an infinite world instantly becomes Terraria-like. Our goal is to put those fears to rest both with beta and with our upcoming videos. Stay tuned!