I believe shadow of the tomb raider is the first game to use ray traced shadows. A comparison of the quality with and without ray traced shadows can be seen here : https://images.nvidia.com/geforce-com/international/comparisons/shadow-of-the-tomb-raider/shadow-of-the-tomb-raider-shadow-quality-interactive-comparison-001-ultra-vs-low.html

(Ray traced version has lot more soft shadows)