I'd really like to use OneFolder, but my phone camera, my camcorder, and my dedicated camera all use different ways to store the image date, which messes up the calendar view, and any view in general honestly.

A solution, as some use "creation date", some "date modified", and some "date taken", and to have software decipher what's the real date is madness, would be to let the user choose on a per folder basis. It's typical to still have the different devices differentiated through folders inside the "one folder", so an option to sort all images inside a chosen folder by a certain date-tag could solve this issue. So there would be a "one date", that represents the real date metadata of the date the image was took and you could just sort by that in the global view.