What was Ryan supposed to do? Tell the moderator to shut up? The setup was bad in the first place—sitting down, the biased, idiot moderator, no rules...
Ryan should have called Biden on his repetition of the lie that Obama pulled the country back from the brink.
Biden came across as a belligerent drunk and it is hard to argue with a drunk. Best to just let him finish
Yes, Ryan should have told the moderator to shut up. Not in those words, but he should have had a really good line ready. Her behavior is not a surprise.