Woe to those who call evil good, and good evil; who substitute darkness for light and light for darkness; who substitute bitter for sweet and sweet for bitter! Woe to those who are wise in their own eyes and clever in their own sight! Isaiah 5:20-21 NASB

If God calls it sin, your opinion does not matter. The prerogative to define truth and sin lies with the Creator. The opinion of the created has no standing.