Perhaps "no evidence" would have been better phrasing than "no reason"? I do think it's possible that some Chinese (or American, or British, or ...) military officer has at some point wondered if coronaviruses would make good bioweapons, but there's still no evidence.
They don't seem like obvious candidates to me, though. Both SARS v1 and SARS-CoV-2 show unpredictable, stochastic person-to-person spread, via super-spreader events. For a bioweapon that would ideally infect all the enemy but no one else, that's the last thing you want, hard to reliably get started and hard to reliably stop once it starts. So that reinforces my belief that if SARS-CoV-2 was of unnatural origin, it was almost certainly an accident during basic research.