I'm using Microsoft Windows 11 Home Version 10.0.22621 Build 22621 and As per here and here, I've already done all of the following but the problem still persists:
(If you're using Adobe Reader, go to HKEY_CURRENT_USER\Software\Adobe\Adobe Reader\DC\SessionManagement instead)
Like you, I tried all the solutions you reproduced without success, on a similar platform (Windows 11, Acrobat Reader 2023.006.20320 64-bit).
Following the first link you put in your post:
(https://community.adobe.com/t5/acrobat-discussions/how-to-stop-quot-reopen-closed-pdfs-quot-message/td-p/11073977), the second answer (from DevilDoc325) is the only solution that has ever worked for me, and judging from your post may not be one you tried.
I do have a simple single user (me) on a personal computer use case, so obviously some people may have reasons not to take this permissions based approach. All I can say is it fixes it for me under my use case.
Recently the registry entries seem to have been moved a little by Adobe and the fix stopped working as described, but finding the SessionManagement key in its new (for me) location under 'Adobe Acrobat' rather than 'Adobe Reader' and following the same instruction seems to still fix it sofar.