The absence of polls never really crossed my mind, but you're right. Of course there would have been more in any normal story of this size.

I found this one from July of 2021: POLITICO-Harvard poll: Most Americans believe Covid leaked from lab. It seems to verify your dates and numbers.

There's also this from the article:

Blendon said Democrats likely became more receptive to the idea after President Joe Biden’s recent order that intelligence agencies investigate the virus’ origin...

As I recall, correct me if I'm wrong, part of the reason Biden had to make that concession was due to the overwhelming evidence presented by DRASTIC.

We've discussed that answer a lot before: if you're part of the Duopoly ruling system, you're not looking to undermine the fundamentals of that system that nurture you - even when you know it's a scam.

And one of those fundamentals is the unquestionable, untouchable authority of unelected, unaccountable experts.