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I can see it being reminiscent, ironically though, I think 6x6 film was around well before polaroid technology.
Personally the 1:1 and 4:5 ratio are my two favorites. 2:3 can be great for a lot of things too. Just a more panoramic look than these others I guess

Absolutely, 2:3 is especially good for panoramas, all the photos we can categorize as postcards. I see the 1:1 format as very suitable for portraits or macros.
Of course, that's my idea!
However, even if you shot landscapes, the 1:1 ratio gives a lot, probably due to the fact that the mountain "soars" the photo.
Good job!