Not anymore. The new Ampere based Quadros and Teslas just launched with up to 48GB of RAM. A special datacenter version with 80Gb is also already announced: https://www.nvidia.com/en-us/data-center/a100/

They are really expensive though. But chassis and rackspace also isn't free. If one beefy node with a couple GPUs can replace have a rack of CPU only Nodes the GPUs are totally worth it.

I'm not too familiar with 3D rendering but in other workloads the GPU speedup is so huge that if its possible to offload to the GPU it made sense to do it from a economical perspective.