If you are going to write anything about AGI, you should really prove that its actually possible in the first place, because that question is not really something that has a definite yes.
For most of us non-dualists, the human brain is an existence proof. Doesn't mean transformers and LLMs are the right implementation, but it's not really a question of proving it's possible when it's clearly supported by the fundamental operations available in the universe. So it's okay to skip to the part of the conversation you want to write about.
The human brain demonstrates that human intelligence is possible, but it does not guarantee that artificial intelligence with the same characteristics can be created.