I don't think one can make that argument about Rodgers. Liverpool was playing for top-4 finishes/CL qualification when he left there, and that is what Leicester is also about, so I think it is safe to say that Liverpool (at the time of Rodgers leaving there) is on a similar level as Leicester is today. So following
@do.ob's logic he stayed at the same level (which is managing a CL-playing club, but not necessarily PL title contender). And I think that is where he belongs - a very good manager for sure, but not one of the absolutely best.
The issue with the Ancelotti discussion really is that none of us can prove what we say - we think that he got only smaller clubs offering him jobs because the big clubs see him as a coach in decline, but obviously we all don't know what kind of offers he really got, so we will just have to disagree on him.