I guess it's not very important what it calls itself. Build 22000 says exactly what you have. For more indications, you might look at the properties dialog (details tab) for (\windows\system32) ntoskrnl.exe and kernel32.dll. I wouldn't be surprised if, even after the official release of 21H2, some things will say Windows 10.
Well, System Info does report it correctly - BUT: uses the same incorrect value/string.
Version should be 11.0.22000 not 10...... and exactly THIS seems the problem.
So all programs which take this value/string (from registry or whatever), will report it as Windows 10.
So, 10.0 is definitely the wrong version string yet! After MS changed it, TCC will report the correct version too (highly probably).
PS: On my Windows 10, I have this at least as following in the registry: