I wanted to compare the prices to the current prices:
> That puts us up to €26,97 a month on our six machines so far.
The cost for this same calculation has risen to €41,94 for the exact same configuration (3x CX23, 3x CX33).
> These two additional load balancers (lb11) bump up the price with €5.39/mo.
lb11 is now €7,49 x 2 = €14,98
> A public IP address costs €1,70/mo which adds an additional €10,20
According to Hetzner's pricing page, this is now free on CX23, but costs an additional €0,50 on CX33.
> ...making our total €47,95/mo pre-VAT
€41,94 + €14,98 + €1,50 = €58,42, or roughly a 22% increase. Still over €10 cheaper than the prices the article quotes for a managed cluster on AWS/GCP, but as someone that does this for a living, €10-15 extra is a very negligible price to pay to avoid the amount of headaches you'll get by having to manage and upgrade the cluster yourself.
Not familiar enough about GCP internal, but AWS prices are way higher than what's quoted in the article. You'll get billed for bandwidth, should you want any logs of your control plane you'll pay them at a premium so high* it will dwarf the cluster price and machine price combined. And for ~$70/month, you get the cluster API, not the EC2 compute required for worker nodes.
* Because vended logs to s3 are not supported (https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/AWS..., https://github.com/aws/containers-roadmap/issues/1141)