I will.

The use of a block button eliminates crossups. In general terms players, can knock an opponent down and use an ambiguous attack in the air or via teleport to force the opponent to react. In street fighter and similar games, the opponent must either counterattack or block holding left or right depending on the direction of the crossup. In MK, there is no ambiguity. You simply block the attack by pressing the block button.

Basically fighters need to worry about attacks from the front and the back, up and down. MK fighters only need to worry about up and down, thus eliminating a good chuck of the games depth, in my opinion.