I would love to use Windows all the time at home but as my Windows 10 installation believes it is up to date (but is clearly an old build number, irritatingly/stupidly only visible in the settings app and not my computer > Properties), it really is not up to date and I have no idea when Microsoft will decide that it is.

It's rubbish. And the lack of consistency throughout the OS (icons different everywhere, duplication of settings app despite same underlying COM snap-ins, settings app titlebar isn't really a titlebar, 3 different right-click menus - one for the Start menu, one for Edge, one for everywhere else) it is driving me insane. You have to learn all of these edge cases on how to interact with core OS windows.

That shouldn't be the case!!

Windows 3.11 came with a manual (I have it) that informed you how to interact with the desktop and windows. Just imagine the mess they'd have to write for Windows 10 - "drag the blue bar at the top, unless it is the settings app, where there is no blue bar and you can't tell where the titlebar ends and the toolbar begins"; "single click on buttons, unless you are presented with the 'open with which app?' dialog where you will be able to double-click on the button that has the name of the application you wish to use" etc etc etc

EDIT: And I say all this where I use my PC all day at work as a C++ Windows dev and Windows at home when I need to cross-compile. Don't get me started on the lack of future for the MFC codebase we have at work.