Not a rendering benchmark but Anandtech has a performance review for each. Looking on the massively multithreaded workload side having 64 cores seems to far outweigh having 8+2

https://images.anandtech.com/graphs/graph15578/115097.png

https://images.anandtech.com/graphs/graph17024/117494.png

You can dig into other benchmarks in the reviews https://www.anandtech.com/print/15578/cloud-clash-amazon-gra...

https://www.anandtech.com/print/17024/apple-m1-max-performan...