Which will always look suspicious, whether it was actually a completely natural virus or not.
Wouldn't the Wuhan lab be able to disprove this really easily? How often do they sequence viruses? Couldn't they show categorically that COVID-19 is not a descendant of a virus they were working with/on?
I think historians in a million years will snort from laughter when reading "The WHO that denies the existence of Taiwan determined that COVID19 did not originate from the bioweapons lab in Wuhan researching that very virus, only in the city".
And if they had such a central database, we'd have probably heard about it by now.
The Chinese authorities are not stupid. They know how bad it looks to not allow investigation. Which means they think the result of a free investigation would look even worse.
It is not feasible to do this probably. The WIV even claims to have completely consumed all biosamples related to RaTG13, which is the most-closely-related known virus to SARS-CoV-2. Supporting such an investigation is completely counter to their interests (speaking both of the institute and the CCP).
The overwhelming evidence is that SARS-CoV-2 emerged completely adapted to humans. This has been confirmed by the amazing lack of initial adaptation to the new human host. We only saw major changes in the spike resulting in a change in phenotype later in 2020. The proximal origins of the spike protein suggest a primate or human host. For this to happen, a natural origin in another species is astronomically improbable. It's the strongest evidence that we'll ever have as to the origins of the virus, and to this biologist it is completely indicative of what happened. We will only know the full truth if people speak out.
Consider for a moment the propaganda value of being able to say, "we visited their labs and witnessed first-hand their failure to {do some sanitization procedure} correctly! Oh how they clearly don't value human lives!"
https://www.researchgate.net/publication/349073738_An_invest...