The greatest advantage of pike is it's great reach, and the greatest advantage of a pike formation is to use that great reach to form an (almost) impenetrable wall of spear points. Then it doesn't really matter if you can't deliver as big a wound to the enemy when the enemy can't even attack you.

Then again in a pike-on-pike engagement where the pikes are of equal length there were casualties and there were instances of thinner ranks holding deeper ranks for a long time and even winning, so at the very least the pike can do damage and the formation did not purely rely on weight of the push.