Because the misspelling reF:kmk was registered on a certain page https://osm.mueschelsoft.de/taginfo/newkeys.htm and taginfo.osm.org then additionally displayed a ratio of 1 to 2 between the two keys ref:KMK and ref:kmk (yes, with cross-checking in the same area; I did not note the exact values). Do you have any evidence that this correction contains an error?