So? When you play Chess at my house under my rules, all my pawns have the power of queens, and my queen has all the normal powers, plus it can move like a knight. If I beat you, is that a legimate victory? No, you didn't have a level playing field because of my rules. Now, it's not the fault of the Yankees that they were given an unfair advantage or that they took advantage of it, but the inequity exists, and whenever an inequity exists in competition that is supposedly based on fairness of opportunity, then you don't get a true outcome. You get a delegitimate result.
I think history speaks volumes about how wrong this statement is. For decades, the Yankees have enjoyed the benefit of playing in the premier resource market for the entertainment industry. Prior to the amateur draft, they had the most farm system teams that horded the most elite young talent, and they won the most championships. Since the beginning of free agency, they have consistently either lead or been near the lead in total team salary, and they have won the most championships. Clearly, neither of these things correlate perfectly to winning championships, because if they did they would have won #27 long ago, but the evidence is clear that their advantages lead to more success on the field.
They had to go out on the field and win the games? Well, duh. That doesn't change the umimpressiveness of the accomplishment when their advantages are taken into consideration, just like it wouldn't be impressive if I beat you in chess under my "house rules".