Your definition is closer to ASI than AGI. And that's the explanation for your first sentence: it's not well defined because you ask 10 people and get 12 different definitions. And it gets even worse if you ask experts in the field :)

Then you have the process of drifting definitions (or, more colloquially moving the goalposts). Hassabis has said this himself: his definition of AGI has shifted. And we know that's true, because we have his definition from 2010 when he started DeepMind. His definition then was much much "simpler", and there are arguments to be made that we already have that. But, alas, he's changed the definition. As did most of us. Seeing the progress will do that to you.

Even going by your definition, even adjusting it for "General" instead of "Super", it's still not clear. What's better? Is a poem written by a nobel laureate better than one written by a lit student? Probably. Is one written by a nobel laureate better than another written by another nobel laureate? Maybe? Is the one scribbled on a card by your 5yo for your birthday better? It most certainly is better for you. And so on...

We're not dealing with easy to define things here. Hell, I could make arguments that every word in Artificial General Intelligence is so hard to define or ambiguous that you'd never reach a consensus between a group of people. There are good arguments to be made in ever each direction. That makes it by definition not well defined. It's all ... relative :)