And humans are often wrong both when we say we don't know, and when we claim to know. There likely is a difference in degree of accuracy, but the point I was making was that despite your claim to "certainly know what [you] know", we don't in fact know what we know with anything remotely near precision.

We know some of what we know, but we can both be pressed into doing things we are certain we don't know how to do but where the knowledge is still there, and we will confidently proclaim to know things (such as the extent of our knowledge) that we don't.

I will agree that LLMs need to acquire a better idea of what they know, but there is no reason to assume that knowing the limits of your own knowledge with any serious precision matters, given how bad humans are at knowing this.

So much of human culture, politics, and civil life is centered around resolving conflicts that arise out of our lack of knowledge of our own limits, that this uncertainty is fairly central to what it means to be human.