So you admit that you're out of your field but then go on to opine about how the scientists that actually are in the field are doing something wrong, and denigrate the predictions they're making as "just simulations" without any experiments. According to you all those smart scientists working on climate change have never thought about the problem with computer models, have never run an experiment, have never thought about statistical confidence intervals for their predictions.

I think you keep bringing up the nitpicky point about diamond to make this guy look dumb. But just like you can call out this guy on the diamond thing climate scientists call each other out in peer reviewed articles when they make weak assertions, that's the scientific method. Among the scientists that actually know what they're talking about a consensus has formed and they are trying to ring the alarm bell. It is dumb and arrogant to ignore them.