Brian, I looked again at your post from the 5th of January: In Photos, names of imported files revert… - Apple Community
You are showing two screenshots, in screenshot one you are saying the changed meta came through correctly, in the second not.
What is puzzling me, is that in both screenshots the info panel is clearly showing the correct filename. The filenames have been preserved. The problem is, that something has added titles in addition to the filenames. Pleas compare:
The second line of the Info is showing the filename -
- "New 093Colours ONC.jpg" for your first example
- "New2023Colours7.jpg" for your second example.
The filenames have been preserved for both images.

The only difference I can see, is that you are not seeing "New2023Colours7.jpg" below the thumbnail in the second example. That is not surprising, as the title is shown below the thumbnails, if a photo has a title. And you can see, that the second photo has a title - the title is not empty like for the first photo. The title "IMG_9209" is shown in the first line of the Info panel in the first line.


Erase the first line, and Photos should revert to using the filename below the thumbnail of this photo to show below the thumbnail.
The mystery remains, what has added the old filenames to the title fields of some of your photos. Photos does not do it - it must have been some third party software. I wish Photos would add filenames to the title field, I have to run an Apple Script to get it done.