Actually, I happen to daily drive both Mac and Windows 11, side-by-side. I also happen to have a monitor that is actively switched between Windows 11 and the Mac, whichever I happen to be on at the moment. So any active machine I'm on has dual external monitors, but the inactive machine only has one. I just timed how long it took for each system to reconfigure when I switched monitor inputs from the Mac to Windows and back, and it was under 2 seconds for Windows and 8 seconds for the Mac, and all available monitors for the Mac go blank for part of that time. This doesn't happen all the time, and I haven't quite figured out what circumstances lead to that behaviour.

I do acknowledge that if the Windows system is the "inactive" one and I open an app that last opened on the monitor which has been inactive, it will open the app on that space. But I find the slow switching on the Mac more annoying. But not nearly as annoying as it spawning random spaces when I wanted two apps on the same space.