Instead of contributing effort to the clan, we now extend that to contributing to society. Today, every person in a modern society must eventually define his or her own purpose in life, either implicitly or explicitly, consciously or subconsciously. In defining our purpose in life, we inevitably bump into our meaning in life, our inner significance. In answering this, we usually end up broadening the question. What is the meaning of my life, leads to what is the meaning of human life, which leads to what is the meaning of life.
Meaning requires an perceiver.
So there is meaning to the question of the meaning of life. Significant to anyone capable of asking it. Yes, there are many meaningful answers, but no meaningful definitive answer. Of course what that meaning is will continue to be debated as long as there is intelligent life to debate it.