I feel like every time AI gets better we shift the goalposts of AGI to something else.

I don't think we shift the goalposts for AGI. I'm not getting the sense that people are redefining what AGI is when a new model is released. I'm getting the sense that some people are thinking like me when a new model is released: we got a better transformer, and a more useful model trained on more or better data, but we didn't get closer to AGI. And people are saying this not because they've pushed out what AGI really means, they're saying this because the models still have the same basic use cases, the same flaws and the same limitations. They're just better at what they already do. Also, the better these models get at what they already do, the more starkly they contrast with human capabilities, for better or worse.