I found that funny.
I know they don't have to spam dair to hit you, you also don't have to use copy in the first place. If there's a power worth having, like Olimars, or ROBs, or Pits, or Falcos, or what have you, I think that you have to make a decision whether the possibility of being punished is worth it.
You can't say the risk/reward aspect of the move is completely unbalanced, against Falco it's more than worth it to take one Dair to get some Falco Lasers, against GaW it's not worth it to get Key'd for sausages. It's a character specific decision, just because you won't get it for free against everyone doesn't mean you have the right to have it changed, ESPECIALLY considering Kirby is already a very good character and doesn't need changes to his game. As I've said before, Jiggs sing isn't getting buffed any time soon.
Oh and yeah, I saw, you can ledge cancel sing and not get punished for it. Woohoo, you have 1/20th of the stage that you can get a sing off if your opponent is an idiot and runs over to you on the ledge knowing he might get ledgehop sung. I don't see how that's any different from the small chance you might not get punished for landing your copy because your opponent is an idiot and doesn't Dair you, but whatever @.@