In comes Brock Lesnar. He's now in his early 30's and is randomly making a MMA debut. He has a 2-1 record in the UFC and is Heavyweight Champion. Wait, hold up... let me say that again. 2-1... Heavyweight Champion. What? Not even in the WWE can you have three fights and become champion. Where is the depth of skill?
In boxing you have to earn you right for big fights. Not only do professional boxers have over 100's of amateur fights and tournaments prior to becoming professionals, but they have at the very least 20 fights before getting a title shot. Now think of it like this... Brock Lesnar went into MMA and became champion with just 2 wins. Do you think Brock Lesnar could become a boxing champion that fast... if at all? I'd be willing to bet Brock would have less than a 50% win percentage in boxing and I can guarantee you he would be laying on his back if he ever dared to step into the ring with a champion.
The TS of the Boxing vs MMA said it in these 2 paragraphs.
MMA ain't got shit on boxing.