I am a UX & Research manager in a big corporate in Canada and I will talk about this with my team. They will really not understand why the preview version had a superior user experience...
Yes, the preview version was very well integrated and well placed, on the right side. No matter what app we are working with, we click on it, and it opens a pane and it had a solid user experience.
I got this sad surprise in my latest Windows Update and initially I thought that a simple option in the settings menu, will bring it back to the right side as it was before. Sadly not!!
An integrated and practical CoPilot placed where it was before is now a casual app with an inferior user experience....
If users feedback influenced this decision to make it a casual App, then I am puzzled for sure...
And even more puzzling, we did not even think about offering an option in the Settings menu to give the users the choice to bring it back as a pane on the right side....
I can't wait to see my UX team's reaction at work...
So I honestly suggest, from both, a Windows 11 user's feedback and from a UX specialist perspective, to simply offer to users a menu option to bring back CoPilot's experience, if they want to, the way it was before (integrated on the right side).
Otherwise, I doubt that I will have the reflex to use it at home or work the way I used to...
Regards