My own experience: Don't ever trust the Chinese government on issues that could potentially involve the reputation of the party. Note that I'm not saying don't trust what CCP says, ever (sometimes they actually do good things) - just not on issues that involve anything to do with how the world might perceive them.
Which is exactly what this issue is about.
That's not to say we have compelling evidence that this was a lab virus, either. I think, for me, it's a, "we don't know, but I wouldn't be shocked at all if it was a lab virus".
"Lipsitch’s activists (calling themselves the Cambridge Working Group) sent around a strong statement on the perils of research with “Potential Pandemic Pathogens,” signed by more than a hundred scientists. The work might “trigger outbreaks that would be difficult or impossible to control,” the signers said. Fauci reconsidered, and the White House in 2014 announced that there would be a “pause” in the funding of new influenza, SARS, and MERS gain-of-function research." [0]
In December 2017, the US began funding gain-of-function research on these deadly diseases again. This research creates deadly diseases that may not have existed otherwise.
This pandemic has been enough for me to strongly believe that there should be a global ban on gain-of-function experiments on deadly viruses and bacteria. I'd like to help prevent a future pandemic, and that's one clear way we can help.
[0] https://nymag.com/intelligencer/article/coronavirus-lab-esca...
Now, try to apply that same reasoning to your allegation without looking silly. Yes, the USG has secretly run certain aspects of a public biowarfare program - and when it came to light they paid. Boom, they couldn't keep it secret and they couldn't escape the consequences (lots of very damaging legal cases and hearings). Finally, do they have an incentive? No - as I said, it makes no sense for them to reduce the cost of yet another world ending weapon. Now you could point to Russia getting caught with massive stockpiles of Anthrax after they claimed to end the program... but their nuclear program's credibility isn't comparable - they've always demonstrated clear signs of insecurity about it. That isn't the case for the USG.