In private messages outside of work, yes, it comes across passive aggressive and is a hard stop to a conversation. In work context though, it’s pretty common on teams as an acknowledgement, though I still think it’s nicer to use like a heart react then actually reply.

I’d like to think it’s a kind of zero approval gambit, he was once a dem I heard. But I think it’s much more likely he’s literally a Russian asset and the question is how much damage can the American system of checks and balances prevent before the next elections.