Let's be frank, Civ5 and Civ6 AI has been terrible at warfare. I played always war games extensively in civ3 and civ4 and frankly, in civ4, the AI is terrifyingly good at it. Civ5 was a joke (AI cant handle 1upt), in Civ6 it doesnt pose a real threat as well. I for one, am very skeptical and won't listen to paid content creators telling me about the AI.
The first few weeks after release we will hear plenty of 'the ai is so good' simply because people are still learning how to play. You got to give it some time to know what is really going on.