Flavor Ability
If we ran this poll earlier, then some of the disallowed moves in the non-attacking section could have suddenly be allowed, due to people voting for Prankster being the DW ability. (And thus limitations could be made to get those disallowed moves to be allowed, with the enforced rule that they are not compatible with the DW Prankster ability)
Now, there isn't any move in the allowed list that is too strong combined with Prankster, because the list was made with Prankster being normally available in mind.
For that reason, now pushing Prankster to the DW ability really has no competitive use.