I think to be brief you need to be precise and it's hard for AI as it's not sure

I think that's part of it. Humans are definitely much more confident (even when wrong) and don't hedge their bets as often.

I think AI also has a lot of internal conversation - you can see it in the reasoning phase - where it will invent shortforms as it talks to itself. This also makes it really hard to follow AI text because it will often invent its own jargon.