Did you consider that maybe the reason this proposal was written was because this mutation was the most likely way this kind of virus could mutate to infect humans?
I don’t understand why people keep throwing around all kind of unsubstantiated facts like if they suddenly made things clearer.
The facts are not that complicated. Could the pandemic be linked to an accidental leak from a gain-of-function study at the Wuhan lab? Most certainly. Do we have evidence that it did? No, we don’t. Could it come from somewhere else? Sure, it can. Was there a properly done inquiry with full collaboration from the lab and the host country? Absolutely not, China was extremely uncooperative and did all it could to control the narrative surrounding the pandemic.
From that, I conclude that it’s highly unlikely we will ever learn anything definitive. Therefor, discussing this is pretty much pointless.