I see this behavior on two computers (out of fifteen) at the office of one of my clients.
DETAILS
Most of their systems are running macOS Sonoma (latest 14.5 release) and Image Capture works correctly--displaying custom printer names. However, on two computers Image Capture displays default printer names instead of the custom names configured on the printers. This behavior occurs when logged in using the user's account. Both machines, though, also have an IT login account--Local Admin. When using this IT account, Image Capture works correctly, showing the custom printer names.
OTHER NOTES
(1) the user accounts on these computers have been migrated from previous hardware as well as previous macOS operating systems;
(2) the IT account was created new on these computers;
(3) after creating a new Test user then logging in as Test, Image Capture works correctly;
(4) duplicating the home folder of a problem user and assigning this duplicate home to a new Test2 user exhibits same problem in Image Capture--default printer names.
(5) removing everything possible from the Test2 user home folder (including most of the Library contents) still results in problem with Image Capture.
Since I cannot remove everything from the Library in step 5 above (macOS restricts deleting certain folders) but have removed all of the folders' contents (including hidden files), it appears something user-related causes Image Capture to display incorrect printer names but I am unable to troubleshoot further. I am limited by time and restricted from making too many changes since these systems are production computers.
CURRENT STATUS
I have an open case with Apple investigating this issue. If there is a solution I will report back.