If the reports that he tried to abduct another child are true, then obviously, something should have been done.
Otherwise, although I never met him, if he just seemed odd, but never tried to harm anyone (that anyone was aware of), I really don’t know what could have been done.
We all know people who seem very odd (at least I do), and we try to keep our children away from them, but what else can we do?
Keep in mind that the vast majority of “odd” people are probably completely harmless.