This is tangential, but I've noticed a trend with this argument and other debates in biomedicine where there's a particular form of appeal to authority that takes the form of immunity by authority. That is, "anyone who is not credentialed in X cannot criticize the practices of those in X."
This assumption, if accepted, creates a sort of a ethical-logical problem where a class of experts cannot be criticized by those outside of the field, leading to an inherent conflict of interest in issues where the nature of the problem are the practices of those in the field. If everyone in the field is doing problematic thing A, but the only people who can evaluate whether A is problematic, there's no way to change the field.
It's basically like not only letting criminals be police and judges of their crimes, but forbidding anyone who isn't a criminal be police or judge.
I'm not saying virologists are criminals, or even that the lab leak theory is correct, but it's the same ethical dilemma, which is what people are pointing to here. It's also not unique to COVID; it shows up in other issues, especially those surrounding medical practice.
In society we have to prioritize the substance of argument or criticism above credentials; otherwise it leads to lack of transparency. There always has to be an outside overseer.