This suggestion is made with regularity. See this old topic for an answer.
Then. Why has this regularly made suggestion still not been implemented.
That's not a real answer, I made a whole thing about why that old broken "solution" doesn't work: https://itch.io/t/1236107/actual-working-tag-exclusion
I don't know, sorry, but asking this question again and again won't fix the issue. For now it's the only answer we can give you.
Oh ok, it'd be great if it was turned into a feature though..