How does open weights address the issue of nation states injecting covert propaganda into another nation's public discourse?
Propaganda has always been there. The dynamics that allowed for all the fake news articles in 2016 to impact the elections are the same dynamics that allowed the articles in this case (shoddy news editors who aren't even verifying the identity of the authors). We didn't solve the original problem in the decade since - it's not going to be solved and is here to stay. The issue has shifted to who has access to this power.
Some random perspective: For years, I lived in an autocratic country where there was no freedom of speech and the government closely monitored all news agencies/publications in the country (before most people had Internet access). The dialog/debate was the same: "If we give freedom of expression, how will we address all the false propaganda coming in?"
Of course, times changed. They couldn't block the whole Internet, and false propaganda came in. Which version would you prefer - the one where they blocked it (but ran their own propaganda), or the one where they couldn't block it?