No one was hand waving anything. There were studies looking at several attributes of the virus’s genome that concluded (not definitively, nothing ever is) that

No one was hand waving anything. There were studies looking at several attributes of the virus’s genome that concluded (not definitively, nothing ever is) that the virus was probably naturally occurring. Some looked at base pair distributions (some GC to AT ratios are required for stability), others looked for sites where enzymes could splice and whether they were commonly found in this species while others looked for any obviously transplanted. Of all the studies I’m aware of, which isn’t all of them, there is no smoking gun. This isn’t a burning building and that analogy is incorrect. No weird GFP producing genes or any common genetic markers commonly found in lab made species were found anywhere. This isn’t to say it wasn’t a lab leak or that there aren’t opposing theories as to whether such and such base pair distribution is considered normal…but the evidence just isn’t there.