It is indeed very strange and annoying. And I don't remember it being so bad ten years ago (although I had to use witcher for alt-tabbing - which actually worked well, unlike AltTab now). Since Linux, and both OG Mac Os, I am used to having multiple Desktops, in total multiple windows of the same applications (browsers, pdf reader, office, file browser). Mac Os is completely hostile towards doing multiple tasks at the same time, and compartmentalizing them into desktops -- you keep getting thrown around to random windows on random desktops (example if you close a window), it's super difficult to find your windows, it's just crazy. You're afraid of ever moving away from a window.
I think this paradim is also what's makes the Mac OS feel snappy. If basically having multiple windows for one software open is "holding it wrong", the OS is pushing you into one application, one window paradigm. As long as you do that, everything is pretty quick. But don't dare open two browser windows, or even worse, two windows of a word processor. The performance will degrade (and you'll keep searching for your windows...)