(To be clear, Tom Cotton himself says the bio-weapon thing was just a hypothesis[1].)
[1] https://twitter.com/SenTomCotton/status/1229202134048133126
On the other hand the fact that they were researching bat coronaviruses in the lab in the city where the outbreak began certainly is suggestive of a possible lab accident. I doubt we’ll ever find certainty of this though just like the 1977 outbreak of H1N1. Not impossible it’s just a coincidence either (after all SARS and MERS jumped to humans without any help).
https://www.washingtonpost.com/opinions/global-opinions/how-...
However, I will note that a colleague of mine saw the virology institute's location change on Google Maps around this time. Free software legend Eric S Raymond mentioned this on his blog as well [4].
I'm pretty sure the Google Maps thing is a sign that the Chinese leadership heard these bioweapon rumors, and figured the best way to combat them was to require Google to lie about the institute's reported location.
There are plenty of ridiculous rumors on the Internet, why would the Chinese government react so strongly to this particular one?
It could be because the Chinese leadership has something they're trying to hide. But in China things are often censored all over the place with little rhyme or reason as well. "We know this rumor's false and ridiculous, any serious scientist knows it came from some country bumpkin eating an improperly cooked bat, but this rumor could potentially be destabilizing, so let's force Google to tell this lie for us" is certainly a way the Chinese government might think.
Is it created in a lab?
The Google maps thing is pretty weak evidence. It could be explained by the "oh crap people are catching on, we'd better make Google help with the coverup" hypothesis, but it's equally well explained by the "we know it's false, but we'll censor things willy-nilly because we're China and that's what we do" hypothesis.
I don't know enough about mol bio to really understand the genetic sequences.
To summarize: The evidence seems to be inconclusive, but certainly consistent with the possibility the virus is a Chinese bio-weapon. "Coronavirus is a Chinese bio-weapon that somehow accidentally escaped" is a possibly true hypothesis. There's not nearly enough evidence to say for sure. But it's a reasonable possibility, not tin-foil hat territory.
Suggesting it was let out on purpose probably does get pretty close to tin-foil hat territory; it seems hard to figure out a sane and reasonable motive for unleashing this on the world, without also requiring some much bigger, more complex conspiracy (which greatly weakens the prior probability of the hypothesis).
If it is lab-created, it probably escaped by a mistake, or someone not following the rules (e.g. the janitor who's supposed to burn the dead infected research bats sold them to a market instead to make an extra buck).
[1] https://news.ycombinator.com/item?id=22146446
[2] https://news.ycombinator.com/item?id=22147320
They react to all kinds of irrelevant bullshit strongly all the time. It's a gigantic unimaginative bureaucracy. It could very well be some peon 18 levels down doing something done 200 times prior, in response to some news article some other peon has classified as western propaganda.
Are they going to come out and admit that?
Now WaPo seems to be admitting that we should at least consider the possibility that the virus may have originated from the Wuhan Institute of Virology. https://archive.vn/UP6dx#selection-1801.148-1801.176