The point of a default is so there is a forced outcome if both sides can not agree. This isn't forcing you to PvP, its making you PvP if someone doesn't want RP, just as previously if someone didn't want to RP fight, they were forced into it.
^ exactly what Bael said. You are free to RP fight with your opponent, it's only if there is a disagreement over the fighting style that the default comes into play.