Hi Sibro,
Surprise !
The third machine updated from 22471 to 22478 does not show the Task Manager bug nor the Delay on Commands running as administrator. Restarted a few time without any problem.
The only difference I noticed during the W.U. was that on this one the .NET was updated before the new Build 22478 while on the other 2 it was updated after the new Build 22478 was done, not sure if that made any difference.
Also this machine was the last one updated.
I wonder if MS may have fixed something in the W.U. process ?
Possibly both.
They should establish a new badge in your honor "Insider Detective" 😁 🕵️♀️