I can see how that might be the case... for casters, but it doesn't change the fact that it still works contrary to the system set up in place for Melee users.
Positionals are made completely irrelevant by moonwalking. We're talking about willfully eliminating a aspect of the game that encourages the use of skill in favour of increasing the overall game speed. It might not be an issue in a 72 man cluster F*** like seize, but things like this make a huge and rather annoying difference in smaller game modes like 24 man, or Wolves Den.
Also, it leaves the door open to broken gameplay. Speedhacking is easier to hide using moonwalking, and could you imagine if everyone did it? It seems nice for you now since there's only a few people who are taking advantage of it, but imagine if the entire map was full of people who glided around like specters instead of actually using their legs. The game would look and feel broken.