The "lab leak" theory was promoted by the usual centrist dipshits because they believed Wokeness had taken control of the entire public health/epidemiology science community and because the people who annoy them on twitter (by telling them they are wrong, because they are) couldn't possibly be right.
We can all be confidently wrong for dumb reasons, but centrist dipshits - much more than conservatives, because conservatives usually have no idea what The Left is actually thinking about anything - are constantly confidently wrong because the hippie girl in college rejected them and she can't possibly be right about anything.
Slightly more seriously, that The Left must be wrong is a bedrock assumption of The Discourse on every subject. Opposition to the "lab leak" theory was branded Woke because people were pointing out, correctly, that promoting the idea was contributing to a right wing racist scapegoating campaign with worrying consequences for Asians and Asian-Americans, and therefore probably shouldn't be just asserted as true based on vibes.