Oh man, I loathe when I close a Microsoft Excel window on macos and my whole desktop virtual space jumps to some other virtual space that happens to still have an Excel window open.
Only slightly less irksome is that the undo history spans all open documents commingled.
Where has macOS focus stealing let you down other than Microsoft applications?
I think about everything that's not made by Apple focus steals. And Apple allows them.
I suppose that's why they developer liquid glass, if they make the screen unreadable it won't matter that the wrong application is focused.
This happens to me regularly on computers running MacOS, including with system prompts that appear too quick while I'm typing for me to tell you what I even hit enter/space on.
I like to have a new Emacs frame pop up for Org capture, but when the frame closes, focus is then given to Emacs instead of being restored to whatever I was using before I used the global hotkey to summon the new frame for the Org-capture buffer.
I have the same problem for opening any text file in a text editor from a separate terminal emulator. If I have any other editor windows open, if I save and close that file, focus is not restored to my terminal application.
It should be noted that this isn't true focus stealing, which is when a new window (that you didn't ask for) pops up and suddenly grabs focus from what you're doing. This is just macOS' app-based rather than window-based GUI task switching behavior sucking like it has always sucked.
Hilariously LibreOffice steals this "functionality", at least in KDE.
Everywhere. All the time.
It's even more infuriating when I want the focus but because it's on a different space MacOS bugs out and refuses to switch. Not to mention when I have an app set to all spaces and reboot and it's stuck on a single space. Nobody at Apple uses MacOS.
I get various app update dialogs opening up and stealing focus. Fusion360 is pretty bad when you open it - it takes forever too.
Focus stealing happens quite a lot on macOS.
The VPN client I use for work will pop up and steal focus every few minutes if it's running but not logged in.