You give two arguments. One is that some colds in humans are caused by coronaviruses. But on the other hand, coronaviruses cause severe and fatal illness in liv

You give two arguments. One is that some colds in humans are caused by coronaviruses. But on the other hand, coronaviruses cause severe and fatal illness in livestock and are not getting attenuated. The second argument is that over a century ago, an epidemic might have possibly been caused by a coronavirus, and might have possibly become a common strain of the flu. This tenuous and unprovable line of reasoning is exactly what I see as wishful thinking.