The reason this was uploaded in the first place is for the funnies. There is no mixup here, grounded A+B is very much reactable but dis waz onlines hue. But sure i dont completely disagree in another context.
I was talking about this at a recent tourney. The best thing to do after feinting a low is a low. Most lows aren't actually quick enough to properly do a mid, so it seems to work very well where people think they are being clever by predicting a low.
Even things like Raph's 11B or Lexia's FC 3A+BG are usually too slow to actually trick your opponent. Things like The former's WR A+BA Work, but that's mainly down to the follow up looking a lot like the actual full string.