If you've updated to macOS Big Sur, have your DisplayVendorID-* file ready but can't copy it to /System/Library ,try /Library folder instead:
/Macintosh HD/Library/Displays/Contents/Resources/Overrides/DisplayVendorID-*
Then restart your mac and your monitor would show the correct colours :)
This works guys Thanks to erfanglmpr
Tharlynnoo
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