For your use case, imagine if the Window switcher, instead of being instantaneous, was a ~1200ms animation which blocked all key presses during the animation.
In either case that's less than 1/3 of a second. It's nowhere near what you're seeing. I'd be tempted to take the machine to an Apple Store and say "this is broken, please fix it".
Are you using software like Rectangle, Better Touch Tool, etc?