I disagree. We claim that biological humans have general intelligence because we are biased and arrogant, and experience hubris. I'm not saying we aren't generally intelligent, but a big part of believing we are is because not believing so would be psychologically and culturally disastrous.

I fully expect that, as our attempts at AGI become more and more sophisticated, there will be a long period where there are intensely polarizing arguments as to whether or not what we've built is AGI or not. This feels so obvious and self-evident to me that I can't imagine a world where we achieve anything approaching consensus on this quickly.

If we could come up with a widely-accepted definition of general intelligence, I think there'd be less argument, but it wouldn't preclude people from interpreting both the definition and its manifestation in different ways.

Well general intelligence in humans already exists, whereas general intelligence doesn't yet exist in machines. How do we know when we have it? You can't even simply compare it to humans and ask "is it able to do the same things?" because your answer depends on what you define those things to be. Surely you wouldn't say that someone who can't remember names or navigate without GPS lacks general intelligence, so it's necessary to define what criteria are absolutely required.