Without empirical refutation of either general relativity or quantum mechanics, it is the incommensurability between the theories that has most driven theoretical physics forward.

Evidence

Capitalising on incommensurability – Integration and Implementation Insights (i2insights.org)

corroborated: 2 independent passages support this claim
XREF: connects to: Existing theories of gravity and quantum mechanics are inconsistent. — Hawking, Stephen, A Brief History of Time, 37; Unified physics theories may require multiple formulations. — Hawking, Stephen, A Brief History of Time, 11

Unified physics theories may require multiple formulations. (similarity 0.91)
Quantum mechanics challenges previous understanding of the universe’s origins. (similarity 0.80)
Kuhn’s initial concept of incommensurability attracted heavy criticism, leading him to shift focus toward untranslatability and unmappability of scientific terms across traditions. (similarity 0.80)
Future theories must reproduce current experimental results unchanged. (similarity 0.80)
Quantum mechanics is one of science’s most successful theories yet remains profoundly counterintuitive and resists intuitive sense-making. (similarity 0.80)

Unified physics theories may require multiple formulations. #expands (0.75) — Hawking, Stephen, A Brief History of Time, 11