delericho
Legend
I'm the player A in this situation. Flower Hugger linked me this as kind of a "Ha, people on the internet agree with me so you are wrong."
Oh dear. It's never good when advise on a general issue is turned into "proof" that one side in a specific argument is right. I'm sorry that this has happened.
It's worth bearing in mind that "people on the internet" also believe that the world is flat, so that by itself isn't exactly a great recommendation.

The problem with this case is that this is the third session and other players have mentioned to him. Other players including literally everyone in our playgroup. Everyone in our group puts effort and energy into playing and he does not.
Key question: does his not putting in the effort really detract from your enjoyment of the game? Or can the rest of you not just enjoy playing your way and let him enjoy playing in his?
(It's also worth considering that not everyone is equally comfortable in performing in front of a crowd. If everyone in the group is super-excited and outgoing, it can actually be difficult for a person who is more introverted and shy to open up and get involved. And the solution to that it time and encouragement, not criticism and an inquisition. Obviously, I'm not saying that this is the case here - I don't know - but it's worth bearing in mind that people are all different.)