[Arnt]

NAT is bad and massive address spaces, sure. And having massive address spaces is so pleasant to work with.

Should be globally addressable, not so much: IPv6 explicitly includes site-local and link-local addressing. A fridge ought to ask for a site-local address, not a global one.

The core of IPv6's addressing is that if you make the address space large for everyone, even the use cases that don't need it, you get rid of many minor headaches later. Like the sort-of-colleague I have who suddenly needed access to some 186.168 servers from a distant network that also happened to use 192.168, partly overlapping.