One problem --- I can't say "the" problem --- is that the Church stopped leading society several decades ago.  It made the decision to follow instead.  No Church is perfect, not even the one established by Christ Himself.  But no church came closer to reflecting the teachings of Christ.  (If you don't believe this, your claim to be Catholic is irrational.)  Given such a Church, it is absurd that it follow society, rather than the other way around.