Thanks again for your comments. Actually, Microsoft support for Windows 8.1 continues until January 10, 2023. My WIndows 8.1 machine is superfast and I am delaying updating it, because I know that Win 10 or 11 will slow it down.
My Windows 10 machine rebuild is not going well after it crashed. I've got iTunes 12.12.3.5 running but it fails to complete the iOS update on the phone. Maybe today I'll make it work.
My thoughts about the error message are that if they are making changes to the software version, it's part of the quality management process to update relevant error messages. By the way I've worked in the industry for over 30 years and error messages were part of my responsibilities.