That's not a fair comparison, age matters, most people don't get smarter or stronger when they grow old. More fair comparison would be "you can't fight against a child", some children are quite strong for their age, as Mike definitely is for his age, and some eager children would surely want to fight against a professional in his prime. But there's no point for said professional to fight them apart from a show match, and you don't destroy children or elders in a show match even of you can.
Other then the fact of "money" I don't see why Tyson did this. He's a fuckin legend and he knows he's better then this hothead youtuber. Paul his boxing pants are worth 1million because it's full of diamonds. How far from reality do you want to live. But whatever.