I believe the USA has "astroturfing squads" for this kind of work. This is one more evidence of it. Social media is likely flooded with astroturfing activity from the USA government. They also likely manipulate the social media software to help in this. For example, YouTube has a comment filter that automatically deletes comments that contain certain words; because of this filter, if you say certain things, the comment gets deleted, and you don't know it unless you look for the comment. Most comments I make on YouTube about geopolitics get deleted. A way to get the comment delivered is to hide likely banned words or expressions by inserting a space in the middle of the word. For example, the comment "China wages developement. America wages wars." will likely get deleted. To deliver it, you could write "Chi na wa ges developement. Ame rica wa ges wa rs.".
Maybe some info got leaked, it got attention in Asia, and then the USA had to say something. But even if this was the case, it would still be strange that they admited it.