That's not a like-for-like comparison. You need to compare CC to the c8a range of AWS, on-demand only. That's where the 1/3 comes from. For example:

c8a.medium (1vCPU/2GiB RAM/no SSD) on-demand on AWS: 5.39 cents per hour plus egress Carolina Cloud equivalent: 2 cents per hour with zero egress

If you don't have egress then the price is closer to 40% that of AWS. If you do have egress, the price could be far, far below 1/3.

Hetzner server auction is great for many use-cases, but it's not a fair comparison with EPYC Turins.

(1) https://cloudprice.net/aws/ec2?filter=c8a