While I think I understand the argument you're trying to make here, it's not a very good one imo. For example "Ancelotti didn't think his team was good enough to play their usual gameplan against Bayern" is just not true, or at least we don't know if it's true. The only thing we do know is that Ancelotti thought it was better to play against Bayern the way they did rather than the way they usually do. And looking at the games, I think he was rather spot on with that.
And in general that's the crux with your argument in my opinion: If someone changes his gameplan when playing against you, it doesn't necessarily mean that they think you're better. It just means that they feel more confident playing another way, it gives no indication whatsoever about the situation otherwise. It might seem like a small difference, but it's really crucial to the argument here.
Besides, I don't feel as if a managers unwillingness to adapt to their opponent should really be listed as a strength, and the opposite as a sign of weakness. If anything, this is precisely where Guardiola (who I hold in extremely high regard, even though I'm personally no fan of his, far from it) loses points.