This seems to be done voluntarily by NVIDIA, at least partially. While in Seattle I set up geo-blocking on my LAN as an experiment. Later when I tried to create an NVIDIA account I couldn't because it was attempting to store my PII at nvidia.cn. When I changed the url to nvidia.com everything worked just fine. I've always wondered what non-evil reasons one could use to explain that choice by NVIDIA. Ping was at least 2x longer to .cn.