The closest genetic match is only 3.8% similar. When it only has 29,903 base pairs, that's 1,136 mutations. I'm no bioscientist but my friends who are tell me that's a lot of changes, and that experiments might change a few base pairs or proteins at a time. A lab leak theory doesn't explain how gain of function study resulted in so many mutations, unless they were blasting these viruses with radiation, and what would be the point of that? Radiation mutations would cause too many changes to do useful science.
Everyone keeps looking at bats but the closest bat coronavorus is 20 years of evolution away. SARS and MERS came from palm covets and dromedary camels respectively, so what's the deal?
Every time I read about this I keep thinking "huh that's sketchy but circumstantial" and I've yet to find an answer to how the lab would've gotten to this point, undiscovered, with no published papers or research or notes or preprints anywhere