Bill Maher was one of the few kind of honest people on the Left and this exchange sums that up well. 

Because he was willing to listen to other people, accept their premise even when he disagreed, but still continue to chat in good faith. Leftists find that impossible. They let the perfect become the enemy of good enough.

America lost a national treasure. 

Very few people are capable of rational discussions. 

Bill is a bit lit. 

Every time some 'supposedly' heinous quote from Kirk starts circulating, eventually the full context emerges and it becomes clear he was making a truly rational point. They can only defame him by misquoting him. They may be using his 'exact' words, but they aren't repeating the conversation with proper context or the spirit in which it was intended. 

In a perfect world, the public would have realized this before Charlie lost his life.