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.

How does a mid view taskbar help your ADHD?

Visual stimuli in the edge of my field of view really distracts me - if I'm looking at a pair of computer monitors I want any movement or blinking that I'm not expecting to be in the center of my field of view so I can quickly dismiss it. If it's at the edge of my field of view it (i.e. at the top or bottom of my screen) when I focus on it I'll be looking further away from my active work and it is more likely to drop me out of focus.

There is a registry fix for that.

A registry fix that only partially works (the icons get really weird) and one that they don't officially support and may remove at any moment.

I will not doubt there is an issue but I never experienced the it

If you prefer it just imagine I said "'Cus I prefer it" - I do understand that the things that impact ADHD folks differ greatly from the rest of yall and I even am of the opinion that ADHD is probably too broad a grouping and it'd be more helpful if we had specific sub-groupings of different symptoms. For me, if I see a flicker at the edge of my vision my brain will hard dump whatever I'm working on to focus on that and it's extremely difficult for me to resume my work. Whether this is common to all ADHD folks, male ADHD folks, or just me - I don't have a clue... but it is something I've observed about myself over the decade I spent trying to work in busy office environments.

Having a side-docked taskbar is something I find genuinely helpful and I'd prefer that if they're going to take it away they give a compelling reason for it.

There is a case that it should have moved to the side, as a default. There’s more horizontal space than vertical space on every display. So if you need to put something somewhere, put it where you have extra room.

>I have ADHD

You lot are worse than vegans at this point

I don't think this will ever happen as it seems that most of Windows team is busy with putting Copilot in every nook and corner of Windows and others are busy migrating every GUI to WinUI3.