These attitudes create hostility and often make combined activities impossible. God's intention is unity, as reflected in the Trinity. To say that cultural diversity originates from sinful activities does not mean that the various expressions of culture are necessarily evil. Neither does it mean that the diversity of humanity, as seen in its many cultural expressions, is a bad thing in itself. Nor does it imply that one culture is superior to any other.
All cultures have their strengths and their weaknesses.
Turning to the book of Revelation we see that there will be recognition of cultural and ethnic identity in eternity. Revelation chapters 5 and 7 indicate that there are people from every nation, tribe, people and language worshipping around God's throne. The picture of cultural diversity in eternity is one of unity, worshipping together. Cultural diversity has been redeemed, it has been reconciled, and there has been restoration of fellowship between cultures. The grandeur of the Gospel is that it has in it seeds for the reversal of the affects of Cain's murder of his brother, the Tower of Babel or the foolishness of Noah's son.