I think it is possible that it was/ is a virus that was in the PROCESS of being weaponized and it somehow "got out" into the populace un-intentionally. . . OR, at worse as some form of test run.
Coronavirus (COVID=19) is not that devastating though, as biological weapons go. So far, it only primarily targets and kills elderly (mostly men) who have other underlying health issues they are dealing with.
I doubt very much that China's military strategy or goal would be geared towards knocking more and more elderly off with the result of simply halting their own (China's) production and export capabilities and putting a temporary dent in our entertainment industry and Social Security roles.