DDR5 memory has kits rated for up to 8400 Mbps, while desktop CPUs only officially support up to 5600 Mbps. How much does running at official specifications actually impact performance in common content creation applications?

DDR5 memory has kits rated for up to 8400 Mbps, while desktop CPUs only officially support up to 5600 Mbps. How much does running at official specifications actually impact performance in common content creation applications?