So I generally give like zero weight to conspiracy theories. That being said, I don't believe anyone can reasonably claim with any degree certainty that Covid was a lab-leak BUT the WHO investigation simply hasn't done their due diligence to a sufficient degree to eliminate this theory.

Unfortunately the WHO's credibility is trained here. In the early days of the pandemic the WHO bent over backwards not to upset China. More to the point, it took China's denials on face value.

So it's more than a year after the pandemic started before the WHO investigators got any sort of access to investigate (which, incidentally is not a good look for neither China or the WHO).

But here are two demonstrable and known shortcomings of the WHo investigation:

1. In 2019 there was a database of coronaviruses that China had. In late 2019 it was taken offline. Super-weird timing. By itself that doesn't prove anything but the WHO hasn't investigated it. Did they ask? If not, why not?

2. Wuhan labs do investigate coronaviruses. The WHO has never been given access to what coronaviruses they have.

It is weird that 1-1.5 years later we're still unsure of the origin (unlike, say, SARS or MErS).

Oh and, for the record, I don't believe for a second this virus was in any way engineered.