Despite what Sam Altman (a high-school graduate) might want to be true, human cognition is not just a massive pile of intuition; there are critical
deliberative and
intentional aspects to cognition, which is something we've seen come to the fore with the hubbub around "reasoning" in LLMs. Any AGI design will necessarily take these facts into account--hardcoded or no--and will absolutely be capable of forming plans and executing them over time, as Simon & Newell described the best back in '71:
The problem solver’s search for a solution is an odyssey through the problem space, from one knowledge state to another, until… [they] know the answer.
With this in mind, I really don't see any basis to attack the intelligence explosion hypothesis. I linked a Yudkowsky paper above examining how empirically
feasible it might be, which is absolutely an unsolved question at some level. But the utility of the effort itself is just downright obvious, even if we didn't have reams of internet discussions like this one to nudge any nascent agent in that direction.
[1] Simon & Newell, 1971: Human Problem Solving https://psycnet.apa.org/record/1971-24266-001