I wouldn't call GPT-4 sub-human intelligence. While it's intelligence is less robust aggregate human intelligence, I don't think there is any one person alive who can compete with the breadth of GPT-4 knowledge.
I also think that the potential of what currently is possible with existing models has not been fully realized. Good prompting strategies and reflection may already be able to produce a system that is effectively AGI. Might already exist in several labs.