I can see the bishops not being serious about coaxing folks back.  After all, those who left once might leave again, so they can't be counted on.  And they might question or continue to question and challenge what the bishops say.

The abuse situation may have prompted more of the average pew sitter to pay attention to the broader situation.  Just seems to me, from the admittedly small sampling of family, friends, co-parishioners, and local articles and letters to the editor, that some don't know, don't care, or maybe, as you noted, choose the easier and less challenging path.