Removing the person keyword associated with the name assigned to a face rectangle fails to remove that name from the rectangle, and when the photo is exported, that keyword still gets exported even though it's been removed from the photo.
The bug is not present in LR 6.14 (Win 11) or 10.4, 11.0, 12.0 and 12.1 (Mac 15.7.1). The bug is present in 12.2, 12.3, 13.0, 15.0 (Mac 15.7.1) and 15.0 (Win 11 Intel).
A clumsy workaround for removing the person keyword and name from one or more photos at once, without corrupting the catalog: Place the selected photos in the Quick Collection. Select the Quick Collection. Go to People view. Right-click the face thumbnail for that name and do Move To Unnamed People.
To reproduce:
1. Select a photo and go to Library Loupe view.
2. Using the Draw Face Region tool, draw a face rectangle over any part of the photo.
3. Type "Jane" in the face rectangle's name box and hit enter.
4. In the Keywording panel, delete Jane.
5. Observe that the face rectangle is still labeled "Jane" (incorrect).
6. Export the photo as a JPEG with Metadata options Include: All Metadata.
7. Use Exiftool to observe that "Jane" was exported into the JPEG as a keyword and attached to the face rectangle (incorrect):
$ exiftool -a -G DSC02430-2.jpg | grep Jane
[IPTC] Keywords : Jane
[XMP] Subject : Jane
[XMP] Person In Image : Jane
[XMP] Region Name : Jane
8. Import the exported JPEG back into the catalog. Observe that it is assigned the keyword "Jane" and the face rectangle has the name "Jane" (incorrect).