Personal, professional, political ... could be any one or a combination. I suspect some folks who have been trying to walk a fine line & protect their jobs see that Lord Fauci has been wrong on EVERYTHING, criminal on much, and they don’t want to go down with the Fauci ship.
Up to a point, everything was hunky-dory. Evidently a “line” was crossed.
I’d be interested in what/where that line was.