I honestly don't think that it's that bad.
Shark Boy does a fantastic Steve Austin impersonation, admit that much. I think the music is fucking retarded, but I don't mind Shark Boy doing an Austin impersonation at all. It's something he does well that could help him get over (further) with the crowd. I mean, how much could it hurt someone named "Shark Boy?"
Also, I love the way people are crying "ripoff." That is definitely the wrong noun to use. If they had a seriously wrestler come down to the ring, throw some Stunners, drink some beer, and called him by a name that looked like it was trying to distance the association with Stone Cold, then that could be considered a ripoff. A masked guy pretending to be Stone Cold Steve Austin is not "ripping off." It's an attempt at parody.
It's using Shark Boy as well as he can really be used, I think.