Sure, I get what you're saying. It's still a sacrifice, but the compensation is just mate in 2, so the there's no real "sacrifice" here.

That being said, any sacrifice that doesn't guarantee a better (or at least equal) position isn't a sacrifice either, it's just "hope chess", aka a bad move. In Blitz or Bullet you can make the case for a "bad" sacrifice for positional complexity and putting time pressure on your opponent to make accurate defensive moves.

In the Opera game, Black just played a poor game start to finish. Giving up the bishop for the knight, pushing the B pawn while the king wasn't castled.