You're completely correct, great points. It's very easy to fall into the trap of 'human-like intelligence will fix it' when thinking of better machines, but it's fairly clear that human-like intelligence has a lot of failings too.
even if the hole knowledge graph would be filled out by humans, there would still be errors in it, thats just how it works with this sort of big data. No way you could design a computer algorithm which does this job without a single error
I find perverse pleasure in your ironic error, i.e. a hole in your knowledge (or potentially typing skills) related to the distinction between "hole" and "whole".
I actually tried to imagine a hole-based knowledge graph... it sounds really interesting.