Ryzen 5000 should easily be able to do 3600/1800MHz, possibly even Ryzen 3000. The 2000 series may have trouble reaching 3200/1600MHz depending on the memory setup and chip quality.
Have you actually tried running the memory in 3600MHz + 1800MHz FCLK? The CPU (memory controller) should be the deciding factor of how fast you can run the memory speed and infinity fabric.