What Is the Difference Between Date Taken and Date Modified?
One belongs to the photo, one belongs to the file. Confusing them is why libraries look wrong.
Every photo on your computer has at least two dates, and they answer different questions.
Date taken belongs to the picture. The camera wrote it at the moment of capture and it never changes, no matter how many times the file is copied. This is the one you care about.
Date modified and date created belong to the file. They record what happened to it on this particular disk: when it was copied here, when it was last written. Copying a photo to a new drive resets them. They say nothing about when the photo was taken.
Takeout photos often have no Date taken at all, so your file manager shows only the file dates, which all say the day you unpacked the download.
The app writes the real capture date into both places at once, so the photo carries its own truth and your folders sort correctly too. The first 500 photos are free.