I believe (Matt. 8:21-22) provides some explanation here. "And another of his disciples said unto him, Lord, suffer me first to go and bury my father. But Jesus said unto him, Follow me; and let the dead bury the their dead."
In other words, here the 'dead' are physically alive yet are identified as 'dead'.
So, when (Ecc. 4:2) says, "I praised the dead which are already dead", he is speaking of the dead who have died as opposed to the dead who are still alive. And when it says "more than the living which are yet alive", he speaking of the living which are alive now as opposed to the living not yet alive.
I believe (Ecc. 4:3) supports this when it says, "Yea, better is he than both they, which hath not yet been, who hath not seen the evil work that is done under the sun."
Why would this matter? My opinion at this time is because it identifies the people as the living and the dead even prior to their being born.
Quantrill