Is dual-rank DDR5 worth hunting for gaming?

Probably not. The difference is usually 1-3% at best, and you’d only see it in CPU-bound scenarios with a very fast GPU at 1080p low settings. Real-world, sit-down-and-play? You will not notice. If you’re chasing every last frame, spend that extra cash on faster RAM speed (6000-6400 MHz CL30 is sweet spot) or a better CPU cooler instead.