> There are plenty of viruses from animals known to infect humans
Yes, absolutely. AFAIK that's where almost all viruses that infect humans come from.
> it's exceptional because it can pass from human to human
With extremely high efficiency, from the first appearance of the virus! If it were not already optimal, then the initial transmission rate would have been lower, and the genome would have had to rapidly change in the process of surviving. This was seen with SARS1. It's seen with other epidemics. The fact that it isn't seen here is very, very weird. Why did SARS2 not have to adapt to its new host?
Yes, absolutely. AFAIK that's where almost all viruses that infect humans come from.
> it's exceptional because it can pass from human to human
With extremely high efficiency, from the first appearance of the virus! If it were not already optimal, then the initial transmission rate would have been lower, and the genome would have had to rapidly change in the process of surviving. This was seen with SARS1. It's seen with other epidemics. The fact that it isn't seen here is very, very weird. Why did SARS2 not have to adapt to its new host?