You are not alone. Among other concerns, this is practically my greatest reason to not switch to win11 at home; professionally I use it but I would never choose it for my personal OS.
It's not just your greatest reason, it is the #1 issue raised on Microsoft's own feature request board.
It is a conscious decision, not an accident
Is there a statement why they don’t allow it anymore?
Supposedly, the win11 refactoring of the code base made it infeasible to allow. My hot take on this is if their code is now so unmanageable so as to disallow where a rectangular bar with some minimal interactions is positioned on the screen, it's time for me to get off of it wherever possible.