I see this at work, being within such a customer. People driving these mandates barely understand IPv4, let alone know what IPv6 is. They're software developers after all, not CCIEs.
There's nothing preventing you from having a private network using unique address space that's either blocked from accessing the internet via a firewall on a router or just plain not even routed. You could even use ULA networks with stateless prefix translation to avoid using GUA addressing for your private network.
The sad part is that IPv6 support is abysmal on every cloud so just migrating to it imposes serious limitations as addressed by the blog author.
There's nothing preventing you from having a private network using unique address space that's either blocked from accessing the internet via a firewall on a router or just plain not even routed. You could even use ULA networks with stateless prefix translation to avoid using GUA addressing for your private network.
The sad part is that IPv6 support is abysmal on every cloud so just migrating to it imposes serious limitations as addressed by the blog author.