Sep 14, 2021 - KB5005565 released - Windows 10 servicing stack update (SSU) - security update.

Known side effects	Recommended workarounds (by Microsoft)
“Devices which attempt to connect to a network printer for the first time [STRIKEOUT:might] fail to download and install the necessary printer drivers. [...] This issue has been observed in devices which access printers via a print server using HTTP connections. When a client connects to the server to install the printer, a directory mismatch occurs, which causes the installer files to generate incorrectly. As a result, the drivers [STRIKEOUT:may] not download.”	KB5005611
“Installation of printers using Internet Printing Protocol (IPP) [STRIKEOUT:might] not complete successfully.”	KB5006738
“You [STRIKEOUT:might] receive a prompt for administrative credentials every time you attempt to print in environments in which the print server and print client are in different times zones.”	KB5006670

Sep 17, 2021 - The September update (KB5005565 and KB5005566) may paralyze printers again. HiFiNews.com

“Users said they could no longer use network printers after applying cumulative updates [...]. [...] Documents can no longer be printed via network printers, while the printers will work as usual again if the cumulative update is uninstalled manually via settings or the command line.” “In addition to printing issues, there should be reports of problems with the installation of Windows Update itself, which therefore prevents the update. If you cannot install the update, [...] try manually downloading from the Microsoft Update Catalog.” “Of course, for security reasons, you should still not be able to do without updating Windows, although a small time delay can be useful as error prevention.”

Sep 18, 2021 - Windows 10 and KB5005565, printing and installation bugs appear, solutions – GinjFo Bitonus.com

“The two cumulative updates affected are KB5005565 and KB5005566. After their installation, users are victims of failure. Regarding printing, it is reported that the PC can no longer print documents using a network printer. A workaround seems to work. It consists of removing the cumulative update in question. It works with 'Settings' and a command prompt.” “Along with this printing bug, KB5005565 and KB5005566 are also associated with installation issues. [...] In some cases the situation seems to be resolved by using a [STRIKEOUT:manual] offline process. Clearly you have to download and install the KB manually and not with Windows Update.”

Sep 24, 2021 - KB5005565 network printer woes. r/techsupport

“Apparently wushowhide.diagcab utility allows to prevent specific updates from installing without turning off other updates.”

Oct 05, 2021 - Removing Windows Security Update KB5005565. r/techsupport

“PrintNightmare changes are permanent, removing this is a poor fix and you should look up the various mitigations for it (including disabling the primary issue fix via registry).”

Nov 15, 2021 - How to fix ‘Inaccessible Shared Printer’ after the KB5005565 Update?. AppUals.com

The shared printer access issue after the KB5005565 update (despite the update’s itself incompatibility with the system) was mainly caused by the following:

• Incompatible or Outdated Printer Driver: As the KB5005565 update enabled the new printer technology (replacing the older Point and Print) and the client system is still using the older one, it [STRIKEOUT:may] not be compatible with the KB5005565 update, resulting in the loss of the printer connectivity.
• Outdated OS of the Client System: If the client system is outdated whereas the print host/server is updated to the latest, both systems [STRIKEOUT:may] become incompatible with each other, resulting in the printer issue at hand.

Above are all Google search results I considered relevants, for the expression «intitle:"KB5005565" "PrintNightmare"», written in languages I can understand. Completely ignored, due to the low average quality of content: social networking websites; forums; questions and answers websites without reply voting/replier reputation systems; and email discussion lists.