The lab theory was always considered possible but less likely. It's just thanks to the insane politicization of the issue in the US that some internet "experts" think otherwise and obtain "evidence" from various blogs and fringe scientists.
On social media and blogs the discussion is always distorted. Just don't use them as a source of information - although, to be fair, there were many good pointers to information on HN. Thanks to some hypochondriacs at HN, I was able to predict the development of the pandemic pretty precisely since January 2020. My work colleagues were impressed.
In addition, there was a lot of initial pushback against any lab leak theory from virologists involved in gain of function research (regardless of whether gain of function engineering itself was the least plausible of the two leak theories).
Part of the issue here is definitely what we mean when we say something was 'considered possible' - here I'm thinking quite explicitly of mainstream and majoritarian perspectives since that's what impacts most people who aren't able (or allowed) to meaningfully contribute to a debate on its technical merits.
As for the initial pushback of the lab theory by virologists, I'm not sure what you're trying to argue for, though. Yes, most virologists rightly considered the lab theories way less likely from the start, and I also remember distinctly that some international scientists who had been to the Wuhan lab (or collaborated with researchers from the lab) defended their Chinese colleagues against unfounded allegations in early 2020. This assessment is confirmed by the recent studies mentioned in the above linked article.
Even if you think they got it wrong and these studies are not as conclusive as they claim, I don't think you can fault virologists for voicing their informed opinions about what they overall consider most likely. It is in the nature of scientific work that you consider some hypotheses more likely to be true than others.
Discussion was driven underground, which is why D.R.A.S.T.I.C. (who found most of the evidence for it) was made up of anonymous people. Chasing this story resulted in a New York Times reporter being fired; his investigation eventually had to be published on his own Medium blog and in some physics journal.
The lab leak theory was utterly and completely squashed in the public realm by nothing more substantial than a bunch of virologists saying "it wasn't us". Trying to claim it was never suppressed is an Orwellian attempt to rewrite of history.
Actually more often it was the opposite—the open possibility that it leaked from a lab, was used to prop up assertions that it was engineered in a lab.
Of course it wasn’t. On one hand, there was no evidence of anything either way—partially due to the situation, and partially due to China not wanting to answer any questions. And on the other hand, half the country was trying to use any possibility as a wedge to say “look China causes this on purpose as a deliberate attack!”
At no point was there a possibility of open debate.
Honestly, there still isn’t—there’s no good evidence in either direction, so it’s just people shouting their side’s talking points at each other.
My recollection is that one "side" was arguing a very different thing than the other, and never the twain shall meet.
The bottom line is we will never know, since China is not exactly a free country were potential eye witnesses can be interviewed freely. The market theory was always more likely and more dooming for China, though. It's easy to beef up the control of bio labs, it's way harder to close down all animal wet markets. Officially, China claims they have done the latter but I've heard that they continue to exist all over China.
Secondly, it was suppressed in the way that news media and Twitterati were labelling everyone considering this theory as a possibility to be racist because some racists they know also shared the same views.
"The market theory was always more likely and more dooming for China, though"
No, the most likely possibility from day 1 was that a novel coronavirus emerging right next to a lab doing experiments on novel coronaviruses came from that lab. It was always nonsensical to claim otherwise.
The other side just engaged in, labelling, name calling and ad hominem attacks which is what added credence to this theory in the first place..