Here is the problem with your argument. There are wet markets in every city in asia, and the animals sold in these markets are from all around South East asia. For every single spill over that has occurred prior to SARS2 there were multiple independent outbreaks overtime, this is because the virus is circulating in an animal species, and this happens regardless if one of the viruses has spread to humans. It's hard to imagine how no closely related virus has been found in wet markets in bordering nations that researchers are actively studying.
Another problem is when spill overs do happen, the virus rapidly mutates as it adapts to humans from a virus adapted to another species. It was due to these mutations that allowed researchers within months for both SARS1 and MERS to track down the animal responsible for the spillover(this is known as the proximal origin ). For SARS2 there virus seemed already completely adapted towards humans, and in fact had more affinity towards human receptors than all other candidate animals tested. You'd think with the 80K animals tested and all the environmental samples taken they'd at least find SARS sequences with distinct animal markers.
One last thing when you look at virology research, for years FCS(furin cleavage site) as been a key area of focus due to it's key role in allowing the virus to enter cells. But for some reason when the head of WIV published a report on the SARS2 genome, she neglected to point out the FCS despite it being a major focus of her and many collaborators research for years prior.
Another problem is when spill overs do happen, the virus rapidly mutates as it adapts to humans from a virus adapted to another species. It was due to these mutations that allowed researchers within months for both SARS1 and MERS to track down the animal responsible for the spillover(this is known as the proximal origin ). For SARS2 there virus seemed already completely adapted towards humans, and in fact had more affinity towards human receptors than all other candidate animals tested. You'd think with the 80K animals tested and all the environmental samples taken they'd at least find SARS sequences with distinct animal markers.
One last thing when you look at virology research, for years FCS(furin cleavage site) as been a key area of focus due to it's key role in allowing the virus to enter cells. But for some reason when the head of WIV published a report on the SARS2 genome, she neglected to point out the FCS despite it being a major focus of her and many collaborators research for years prior.