Just by how they phrased it in their tweet, I think it’s 40 million votes total cast for any game in the Steam awards. Because even if they had sold 40 million copies, definitely not all of those people are going to be aware of the Steam awards and vote on those, you know?
While that's how I read it as well, it should also be stressed that no one needs to own the game to vote for it at the Steam awards, so the direct correlation with sales is tenuous regardless of these being total votes OR votes for BG3.
P.S. That said, I'm still guessing that the game is already the 15+ ballpark at minimum at this point. Of which at least 10 millions on Steam alone.
