Hi Alan,
About 3 computers ago, that happened and I didn’t know why the modified date was kept, but it was the original created date. Thank you for your explanation of why that was. 
However, I have a folder of over 200 images I created in 2017 but except for two of them they all have 2022 dates for both the created and the modified dates in the date colums.
I included the year created in many of my file names because this happened on the last computer too, so for those I at least know the year they were created.
I am dealing with bmp, png, tiff, pdn, pfi, mix, rtg and other file formats.
My jpg images from my camera have their EXIF and IPTC data which includes their created date. But I have at least 10,000 images so this is a real issue for me and I need to find a solution.