Ok, so obviously there are many times when its proper to fold the current nuts in PLOmaha and often PLO8.
How about Hold-Em? I can only think of one:
3 people left in a large tourney
Blinds 200/400
A 15k
B 12k
C 100(after posting)
If A pushes and B calls, its correct for C to fold AA here.
There are a few variations of AA before the flop.

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