Thanks for your following up! And sorry for not linking or proper reply about tag groups before (I was doing another thing at the same time haha and I don’t like to be that way 
)
Now I’m thinking about the best approach for that use case and I’m fully open to read your toughts if you want to share.
Should tags be allowed/limited by lockdown (plus new functionality) before categories?
So, if we got ‘Encrypt plugin - download link’ and ‘Encrypt plugin internal discussion’ threads tagged with
#customization:pluginthey will be displayed in#plugins(trust_level_1 only allowed by category) and#staff-stuff(trust_level_4 only allowed by category).