It's easy to be a critic.

Sometimes, an issue needs to be called out even if you don't have the solution.

Extraordinary claims require extraordinary evidence. You can't hide behind the "go and look it up" response as is often uttered by science deniers.

The extraordinary claim is that the virus was man-made.

Edit to say: I don't think saying the virus came from nature requires any additional proof. The claim that requires extraordinary, indisputable proof is the claim that it was man-made. And I have yet to see it, from this or any source. Just a big compilation of weak, circumstantial evidence.

It's no longer an extraordinary circumstantial claim. It might never have been because this kind of research that very well could cause a COVID pandemic was being concealed by the very people that decided very early that there was no question the origin was natural. They were performing risky and highly similar research and they made huge contradictory statements that conflict with this leaked evidence, and they are very well connected to each other. You are going to need extraordinary reasons why these people don't deserve an investigation into what they had been doing and what they did know that wasn't being shared.

Well while this is not indisputable proof there is a very relevant discussion on virological.org related to both Furin cleavage sites and orgins of SARS-COV-2. The damning part of the leaked research proposal is that they ALREADY had partner researchers located near caves in three different parts of Yunnan Province.

For a more detailed discussion of the origins of SARS-COV-2 while not directly addressing the leaked DARPA proposal please see: https://virological.org/t/tackling-rumors-of-a-suspicious-or...

They also discuss that the base virus was mostly likely linked to bats in Yunnan province. How it got from Yunnan to Wuhan is a matter of question.

However, if the research was being conducted in the US and accidentally leaked into the population it may have been in circulation for sometime (months) before causing serious illness or disease (mutations).