I think the idea is to be able to develop vaccines and treatments against the viruses. That being said it seems like a decent percentage of the medical/scientific community turned against “gain of function” research awhile ago, which is the controversy. It seems like the most likely scenario, in my inexpert opinion, is that the lab was super-charging this virus for whatever reason, it slipped out accidentally and the Chinese covered it up while doing what they could to protect the rest of their country and not doing anything to protect other countries. I’m open to the idea that once they were dealing with it, they purposely made sure everybody would have to deal with it too but obviously don‘t know one way or the other.