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".
Why is it never brought up that it could just be an accident? It doesn't need to be a weapon. Just poor safety during research.
Certain actors have a narrative they would like to push.