Spotlight can't open a folder inside ~/Documents/ I use Spotlight to open folders, but quite often the Finder opens on ~/ instead of the folder I was looking for. I realised it happens when I try to reveal a folder which lies in ~/Documents/. Revealing a folder somewhere else, eg ~/Music/iTunes works like a charm. But something like ~/Documents/foo/ falls back to ~/.
It might have happened for the first time after a system update, a few weeks/months ago. I am currently running macOS 11.2.1.
I suspected privacy privileges, and I reset them with tccutil reset All but it hasn't changed anything.
Interestingly, it seems like I'm not able to change the permissions of ~/Documents/, while it is possible for other folders (see example below).
 Permission management is missing for ~/Documents (left), but is there for ~/Music (right)
Does anyone have an idea to explain this behaviour, and how to solve it? I'll be much grateful for any hint.
Edit 2021-02-15
Out of the blue, I tried something. I used the action Reveal in Finder of Alfred on a folder in ~/Documents/. It worked, and, since that, so does opening folders from a Spotlight search. It must have done something backstage, but I have no idea what. ¯_(ツ)_/¯
There are two questions here:
Firstly, Spotlight always sending you to ~/ (and not the folder you asked for) is I believe a bug.
Update: I have a MacBook running macOS 11.3 beta1. On this the search behaves correctly and Finder opens in the expected folder.  So, it seems this bug is being fixed.
Secondly, my interpretation of permissions for ~/Documents is that Big Sur has taken control of the Documents folder and won't let you make changes.  Unix style permissions and ACLs are overruled by macOS.
There is other evidence for the special role of ~/Documents.  Finder now shows subfolders that are not really inside the Documents folder.  These are folders belonging to some apps using iCloud for document storage.
There seems to be no way of turning back the clock and restoring the behaviour of Catalina and older.  This is just an example of Apple gradually taking away the freedoms we have come to love in macOS.