This is not entirely accurate. Marcion of Sinope did reject the Old Testament believing Yahweh to be incompatible with Jesus. However, he achieved this by teaching a ditheistic worldview in which Yahweh represented a lower, materially oriented God, who was succeeded by a purer transcendent deity encapsulated in the teachings of Christ and the Gospels.
Personally, a more fitting analogy for what you are arguing for, I would think, would be Thomas Jefferson’s approach to the New Testament - literally slicing out the bits he did not like.
For clarity, what exactly do you mean by “the Gnostic impulse to denigrate Creation”?
On an aside, sexuality is a highly charged topic that often overlaps with politics and political discourse. Can we try our best to discuss the OP without sliding into discussions of sexuality, please? Ta.