In every version of Windows since at least 2.0, Alt+Space has worked to bring up the system menu for the current window. This is the same menu you get if you click the app icon in the top left corner.
Once in a while, this has been a lifesaver for me when a window gets stuck offscreen with my multiple monitor configuration. It is a bit tricky, but even if you can't see the window, you can press Alt+Space to open the system menu, then M to select the Move menu item, then press any arrow key, and finally you can use the mouse to move the window around.
Yes, quite kludgy, but this has worked on every version of Windows for decades.
The PowerToys team decided to take over Alt+Space for their own Mac-style launcher, without even warning you at install time that they are disabling a fundamental Windows keyboard shortcut.
This caused me loss of data when I tried to use that trick for a window that got stuck offscreen. I forgot that I'd installed PowerToys a while back, and Alt+Space didn't work to rescue my window!
There have been multiple threads and GitHub issues raised on this, but the PowerToys team has seemed deaf to the problem. They closed one of the issues with a comment like "our metrics show that very few people use Alt+Space for its old purpose, so we felt OK about reassigning it."
I was like, "Your m-----f---ing metrics told you that? Your metrics just caused me loss of data! Do I need to go get Raymond Chen to explain to you the value of backward compatibility?" But I didn't post that, as there is no hope of getting through to people who think metrics should tell them what to do.
Let's say there are a billion Windows users. And only a tenth of one percent know about Alt+Space to open the system menu. No big deal, that's only a million users you have just inconvenienced or caused to lose data.
Please forgive the rant, but I just don't understand that line of thinking.