The stuff in the orange can says it will keep products breathing (so they say). I spray my Rockys at least once a year and haven't noticed any hinderence on their performance.
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Solid old school Baffin Ice Bear rubbers... Good for -40 without liners!
GoreTex, Leather and various so-called breathable materials do nothing useful to "breath AWAY moisture". Nor do they "cool your feet" in the summer. That might be something they can measure in a lab. But in real life it makes no difference.
If you are in water a lot, especially cold/winter season-- get a set of Baffins in rubber that are rated to -100 or more.
For the rest of the year, I do wear leather boots/rubber soled and always treat a new set with silicone spray. It probably helps for the first year and then I always forget to reapply. I'm guessing I could make boots last longer if I sprayed silicone yearly.