I think you're strictly right there. If they'd obtained sequences then they could have built that tree; but as far as I know they didn't, perhaps because the co

I think you're strictly right there. If they'd obtained sequences then they could have built that tree; but as far as I know they didn't, perhaps because the cost of sequencing was higher back then. That's still more evidence than we have for SARS-CoV-2, though. With SARS-1 we had the additional evidence that some wildlife traders had antibodies, presumably from mild infections by related viruses in the animals they handled. There's again no genomic evidence to exclude "reverse zoonosis" there, but the timing seems to make that pretty unlikely. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1140695/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1140695/