[geofft]

Yes, I am. The sort of network architecture you describe works great, but unless I'm seriously misunderstanding the article (which maybe I am!), all the use cases where you'd want VXLAN or Wireguard on IPv4 are incompatible with such an architecture on IPv6.

I will grant that IPv6 + ULAs + BGP + flat networks is easier to think about than IPv4 + 10.0.i++.0/24 + BGP + flat network because you have basically unlimited ULAs, but "You have to pick a unique 10.0.i++.0 for each machine, and that's annoying" doesn't seem like the primary thing the article is trying to forget. If you can do a hierarchical routed IPv6 network, you can almost certainly do it with IPv4, too.