P: v14.5 Lightroom has encountered problems reading this photo | Round circle ‘!’ warning on Images

OS: Windows 11
LrC VERSION: 14.5

A couple of days ago I upgrade to v14.5.
As for every update, I regurlay empty cache, optimise catalog, remove all previews and generate new standard ones (also, I wanted to test how was was the new option to use GPU for generating previews).
Never had a problem with this workflow.
After previews generation process was completed (1h 30m for 29.000 files, 23.000 jpegs and 6.000 raws) I got an error: for 21 RAWs the preview could not be generated. Looking in the catalog at those files, I realised they have an exclamation mark on a dark circle: this is not the missing photo mark. If I click on the exclamation mark, I see error "Lightroom has encountered problems reading this photo, you are not allowed to edit this image. "

Yet, I can still enter develop module and edit the photos without any problem: the editing history is there, I can zoom in at 100% (generating the 1:1 preview), I can change sliders, export... Everything... (PS: I do not use smart previews).

The 21 problematic photos are in different folders and have different dates.
The files can be opened by any other program, including Fast raw Viewer.

For a couple of problematic photos, I tried deleting the photos from file explorer, and the square light missing photo question mark replaced the round dark question mark.
I restored the files from three sources:
1- the original file
2- a backup from a second HD
3- a backup from Amazon Photos

In all three cases above the black round exclamation mark came back: this should prove that it's not a problem of corrupted files, I instead believe it's an issue in LrC.