you would think they could figured out that programs not directly opened by the user shouldn't be able to steal focus from the program the user is currently interacting with. seems like basic UX/UI failure
You're talking about people who haven't figured out you should be able to edit the options on the right click menu from a single settings menu and that the task bar should expand and contract dynamically with the number of open windows. Microsoft stopped improving the Windows UI around 2006.
This is actually pretty hard to get right. Just yesterday I was confused why opening my text editor under KDE didn't pop up a window. Turns out some update to KDE's focus stealing prevention (or some other involved component) changed things so the new text editor window got pushed behind existing windows.