This is a nonsense argument.
A largely identical squad finished mid table last season, under a far better manager (Ancelotti). Do we agree?
Another manager, better than Ancelotti, is not going to come to us in our current situation. Agreed?
Another manager, nearly as good as Ancelotti, is not going to come to us at the moment. Agreed?
A lesser manager, be it Benitez or someone else, isn't going to get as much out of this squad as Ancelotti, or an Ancelotti-level equivalent would. Agreed?
But you don't want to change any players, EVEN during a transfer window???
Name me a realistic candidate to join us as Benitez' replacement in the next three weeks (presume you want a new manager to make their own mind up about bringing in new players?) who is going to get these players back to the dizzy heights of mid-table that they achieved under Ancelotti. Please.