Does the current AI give productivity benefits to writing code? Probably. Do OpenAI engineers have exclusive access to more capable models that give them a greater productivity boost than others? Also probably.
If one exclusive group gets the benefit of developing AI with a 20% productivity boost compared to others, and they develop a 2.0 that grants them a 25% boost, then a 3.0 with a 30% boost, etc...
The question eventually becomes, "is AGI technically possible"; is there anything special about meat that cannot be reproduced on silicon? We will find AGI someday, and more than likely that discovery will be aided by the current technologies. It's the path here that matters, not the specific iteration of generative LLM tech we happen to be sitting on in May 2025.