One area that I’ll give credit to those hacks behind Friendship is Witchcraft is that they correctly point out how RD and AJ’s elements are reversed, with RD more suited to honesty, and AJ more suited to loyalty.
About the only argument against the costume you could make is to say that it might be a nasty reminder to Luna of what she (as NMM) tried to do to Dash. But Dash didn’t know Luna was going to show up, so nope, it’s just a costume that Dash thought would be scary and cool.