How much Lauda's tags need to be replaced?
Perhaps none, since Lauda has been out of DT a few times already and the world did not end. I doubt that any one person in DT is irreplaceable. There is quite a bit of redundancy. Also keep in mind that all those scammers tagged by Lauda won't automatically start to scam the minute Lauda is out of DT, nor are Lauda's ratings disappearing - just moving to the "Untrusted" part for most users, except those with custom trust lists.
For my very own experience with a Lauda feedback, I would say there is a very good chance Lauda made adjustments before he ceased to exist in the Lauda form, or maybe I just got lucky that he kind-heartedly reconsidered adjusting his feedback to me.
Everyone will suggest some sort of change that will benefit them personally.
It doesn't cost anything to keep trust or keep feedback for a person even years after they stop posting. Each person should have the right to ~exclude whoever they want to silence from default trust, and each person can decide for themselves when old trust becomes irrelevant.
Made me remember that verryyyy longgggg listttttttt of I think it was called SMAs or sMAS( Signature Manager Against Sp--eech, i mean Spam.), time flied and it seemed that the SMAS no longer have a use, or I might be wrong. lol