The most popular human origin theory was a lab leak. It was easier to argue against the crazies claiming a bioweapon so that's what most did and that's what got the most press. But the primary human origin story was an accidental release.
Bioweapons research and got infected in a lab that was at BSL 2 ARE incompatible. If you expect it to be able to infect humans, you are going to take more precautions.
The theory here is that they were doing research on animal models and didn't think that humans could catch it from mice. Therefore they took too few precautions, and it escaped through them.
