The only recent evidence it contains is the fact that 3 researchers from WIV sought hospital care back in autumn of 2019 with symptoms similar to COVID. However, this piece of evidence is hardly consequential without further details:
- First, most common symptoms of COVID are indistinguishable from common cold. If the researchers were known to have any "signature" symptoms like loss of smell the article would certainly mention it.
- Second and more importantly, China doesn't have a robust GP/family doctor system found in western countries. As a result, many people would go to hospitals directly whenever they're mildly sick.
Taking the evidence as we know it now, the straightforward explanation is that 3 researchers caught cold, got mildly sick, so went to the hospital to get prescriptions or doctor's notes for sick leave (in China it's common for employers to require a doctor's note even for a short sick leave).
That said, I believe the lab leak theory is still plausible, and shouldn't be ruled out unless a clear transmission path from bat to human has been identified (which was done for the 2002 SARS outbreak). But I also think that we may never know. I trust that some theories put forward were in good faith, but so far they are little more than speculations.
And then there's the completely over the top narrative building based on non-evidence (which also swings wildly based on current trends), legends about mavericks doing secret fact finding missions online etc... stuff that should stay in a bad movie script.
At the end of the day I still think the facts will come up with enough time. If for example the hypothesis is that it's through GoF research, then a group of experts can examine the plausibility and the genomic evidence, try to replicate some of the possible steps etc. Real world research is hard and incremental, it's not done with black magic no one can find out about.