As for the left, well I am not sure there is an official position other than waiting for more data. China is definitely sus but they are always like that from a western perspective so I don't know that I weight it much.
Other than the smugness in watching the right be wrong again, I am not aware of anyone on the left that is invested in either outcome.
It's a matter of waiting for the crucial data being found. How long did it take us to pin point the source of other pandemics?
This stuff takes time.
Internet speculation only takes seconds.
Of course this is all just silly bullshit. I have some inkling of hope that the truth will be made plain, but that's so implausible given current regimes and political paradigms that the only reasonable thing to do is ignore whatever is concluded, at least anytime in our lifetimes.
It's a political topic, so it naturally has positions staked out by both sides. There's not much reason to care about it one way or the other unless you have a tribal viewpoint.