Except Notch's exact words were:
Yet you said:
He didn't even say "monopoly" unless I'm just missing something. Where did he even say something to match your 9/11 paranoia comparison? Saying "I do somewhat worry about X happening" doesn't sound to me like paranoia or panic to me. It seems like a somewhat reasonable concern, if unlikely.
Obviously he's in a good place in terms of supply and demand, and obviously there doesn't seem to be a reason to lower the price when it's selling well (see also: ArmA II on Steam and its reduced sales compared to other games), and obviously he likes making a steady stream of income off the game. It just seems reasonable to me, and the suggestions of him having some sort of monopoly by trying to sell his own product on his own store are boggling my mind.
single entity that owns a gaming platform is pretty synonymous with monopoly.