This 2016 patch is showing relevant on 2019 servers and failing, as it should obviously.
I see someone else posted a similar issue for a different KB.
This is the 2016 patch I’ve noticed with this issue so far in testing…
MS21-OCT: Cumulative Update for Windows Server 2016 - Windows Server 2016 - KB5006669 (x64)
(name of it = “Win2016” OR name of it starts with “Win20” AND (exists value “CurrentMajorVersionNumber” of it AND value “CurrentMajorVersionNumber” of it as integer = 10) of key “HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion” of native registry) of operating system