UPDATE: IPv6 load balancer endpoints are now GA.1 However, we continue to work on instance-level v6 addressing. Since I believe that at least some votes on this issue are for v6 all the way to the instance, I am leaving this issue open.Jon Cutting commented
AWS allows us to configure IPv6 to their EC2 instances, and it rocks. I was really surprised to see that GCP does not yet support this feature. And a bit disappointed in truth, as it means we can't use GCP for a particular use case.