This piece on Pope Francis’s speech before the U.S. Congress is the best thing I have read on the problem with the pontiff’s approach:

The Pope’s recent address to a joint session of Congress was greeted ecstatically, though (or perhaps because) it was notable mainly for its secular rather than for its religious pieties. It was the speech of a politician seeking re-election rather than that of the spiritual leader of a considerable part of mankind; as such, it seemed like the work not of a man intent upon telling the truth, however painful or unpopular, but that of a committee of speech-writers who sifted every word for its likely effect upon a constituency or audience, appealing to some without being too alienating of others. If ex-President Clinton had been elected Pope, he might have made the same speech, so perfect was its triangulation, so empty were its high-sounding phrases.

Pope Francis is not a subtle thinker, let alone a theologian of distinction…There was nothing of timelessness in what he said but only of the temporal, the contingent, the fashionably platitudinous. He is not a shepherd, but one of the sheep.