AGI means what it says on the tin: Artificial General Intelligence. As opposed to narrow AI, which most pre-transformer AI research was, that can only do specific categories of tasks. ChatGPT is a general-purpose NLP interface to a model which is able to be solve any category of problem that can be expressed through human language, which as far as we know is full generality.
What you are getting confused about is that there is a segment of people that have purposefully confused / conflated ASI (artificial SUPER intelligence) with AGI, due to their own beliefs about the hard-takeoff potential of AGI. This notably includes the founders of OpenAI and Anthropic, and early backers of OpenAI prior to the release of ChatGPT. Through their success they've set the narrative about AGI, but they are doing so by co-opting and redefining a term that has a quarter century of history behind it.
The core mistake started with Bostrom, although to his credit he is very careful to distinguish ASI from AGI. But he argued that once you had AGI (the ability to apply intelligence to solving any problem) you would rapidly get ASI through a process of rapid iterative design. Yudkowsky took those ideas a step further in his FOOM debate with Robin Hanson in 2008, in which he argued that the AGI -> ASI transition would be short, measured in months, weeks, days, or even mere hours. In 2022, six months prior to the release of ChatGPT, Yudkowsky has a public meltdown in which he asserted there is no time left and we're all going to die, after having been privately shown an early version of ChatGPT.
It's almost two years since the release of ChatGPT, which is absolutely AGI by the definition of the people who coined the term and have run the AGI Conference series for ~25 years, or by the definition of Bostrom or Yudkowsky for that matter. ChatGP is general intelligence, and it is artificial. Two years of AGI, yet we are still here and there is no ASI in sight. Yudkowsky was wrong.
Yet OpenAI, which was founded by a bunch of Yudkowsky acolytes, is still out there saying that "AGI" will bring about the singularity, because that was the core assumption underlying their founding and the reason for the investments they've received. They can get away with this without changing their message because they've subtly redefined "AGI" to mean ASI, and are hoping you don't notice the slight of hand.