I don't think you're lying, but I do think that there's a different reason you are skeptical that is deeper and probably harder to express.

"You can't rerun the climate" is a common enough sentiment, but when I hear that from technical people and probe them the same way, most will admit that it's not a logical reason to distrust scientific reasoning, and will come up with some other reason.

Never tried it online though, so maybe I come across like too much of a jerk without vocal tones.

Skepticism is a good thing. Where would we be without it? The earth would still be flat. Why does he have to have some alternative motive for being skeptical? Skepticism is the basis of real science - trying to prove a hypothesis wrong to make sure that it is bullet proof. If it cannot be proven one way or the other, then it is not a fact, it is just a hypothesis.

The danger is when skepticism becomes a positive force that has specific ideas it holds dear, like Man-made Climate Change being a myth or the fact that the world is entirely material. Then it ceases to be skepticism and becomes just another ideology trying to protect itself against the others.