Why Does Windows Cleaning Neglect the Temp Folder?

I've observed that Disk Cleanup in Windows 11 often falls short in effectively clearing the appdata > local > temp folder. It frequently leaves this particular folder untouched even after running. The same issue can be encountered when using the similar option found in Settings > System > Storage > Temporary Files. Despite these files not being locked by any active programs, as I can manually clear them myself, the cleanup process seems to overlook them. Some of these files date back over a month and are no longer considered critical. For instance, there are a few family images I unzipped using WinRAR in there.

In contrast, BitDefender includes an optimizer that successfully clears out the temp folder, removing approximately 80% of the files and folders (though not all).

I'm curious as to why Windows 11 consistently misses out on cleaning a significant portion of this folder during the scanning process, and at times even skips it entirely.