No, 2 anons here are bothered.
It has to mean that our understanding about Mueller is incorrect.
It could mean that POTUS has a different reason for nominating Barr, maybe what he knows will come out at a confirmation hearing.
Remember, facts trump all theories. So if this longstanding relationship is fact, we need new hypotheses to factor it in and understand how it fits.
So there is a bit of cognitive dissonance because we have all harbored specific concepts about Mueller's role and, frankly, character.
Be with it. Accept the distress and let your mind roam on it. Maybe in the morning some new theories will present themselves.