It's intentional, but also a poorly implemented feature.

How exactly are you supposed to cmd+~ on a Danish keyboard? To type a tilde you need to option+¨, then space.

Secondly, switching windows uses a strict ordering, e.g., alt+~ doesn't return you to the previous window (at least that's how I remember it working, can't check it on my Danish keyboard, so how would I know?), but cmd+tab does return you to the previous active application.

I too enjoy the distinction between the two. The lack of grouping on Windows makes window switching get really messy really quickly (especially now with Edge injecting tabs into alt-tab too). It’s one of the things that makes Windows unpleasant to work in for me.

If you miss that on Windows: https://neosmart.net/blog/2017/easy-window-switcher/