I thought it was fairly clear that we're dealing with a Sea of Clouds situation, where people are mostly living on floating islands and the ground is an inhospitable wasteland that we're probably only going to go to for dungeons.

Also, my eyeballing puts the inspiration as much closer to looking like FFX or FFXIII than VII. There's not really anything that rings as VII at all, so I have no idea where anyone's getting that, but some of the creatures look a decent amount like fal'cie, and there were a couple locations that give me FFX Temple vibes (but granted, FFX's temples are all wildly different on the outside so it's hard to describe why), as well as areas that reminded me of Besaid from X and Cocoon from XIII. There's also a kinda hard thing to feel out or quite feel like I'm right about, but the landscapes having a lot of vertical eye-catchers makes me feel more like X and XIII; those are the only Final Fantasies that really went hard on pointing the camera up for big visual moments.

They're obviously going for something original, though. Trying to chart anything based on 'oh this person's Aerith' is just going to lead you sailing off a waterfall at this stage.