1. Importance of stipulation diminished on Raw
The stipulations attached to this Hell in a cell bout held dire consequences and made the match incredibly important. If Shane were to win, not only would the Undertakers Wrestlemania career be over but Shane McMahon would gain control of Raw. So once Shane lost the match, it was assumed that he would be on his way back out of WWE. However the wasn't the case, as the next night on Raw, Vince ended up just giving Shane control for one night anyway.
This completely diminished the importance of the stipulation and almost made the epic mania bout feel pointless. Rumors are also suggesting that Shane will be sticking around even longer and may end up running either Raw or Smackdown anyways. Now while this will help to freshen up the WWE, it will further make the entire Undertaker match redundant. Leading one to think, perhaps the better booking decision would have been to simply have Shane beat Taker at mania.
Regardless of all these minor flaws, the Shane O Mac v Undertaker match was truly awe-inspiring and will likely be remembered as one of the most infamous mania bouts of all time, if only for Shanes legendary leap of faith.