That's just internal networking isn't it? VPC on the big clouds, DigitalOcean, and Vultr. Private Services on render.com.

I remember when Fly.io used to tout Firecracker but that is just a KVM engine, along with QEMU used on a zillion hosts.

What I'd like to see are customer success stories.

Edit: looks like you have to set up your own cross-region links on DigitalOcean and Vultr. So that interests me somewhat. :)