Forcing owners of legacy /8's to give them up is hugely cost prohibitive for them. Various orgs with their own /8's might not announce them, but use them extensively internally.

Also, it wouldn't really help stave off the amount of IP's required, and we'd still be out in months.

You do realize most of the legacy /8 owners are actively using them, right?

I'm sure Apple, Ford and the US postal service are all using all 16 million addresses. The fact is that most intra-network traffic doesn't need an IPv4 address since it'll be NAT'd anyways. So even if Apple has 16 million IoT devices around campus, it doesn't actually need 16 million addresses.

Fun fact, Stanford used to have an /8 but returned it since it wasn't using all it's addresses.

CGNAT prevents users from hosting personal services - its a PitA.

Yeah, I just discovered my ISP (WebPass) has exhausted their IPv4 allocation [1] and is transitioning residential customers to private IPv4 addresses, and I'm not really sure how to set up a VPN on IPv4 now. I guess I need to set up a tunnel over IPv6 somehow?

1. https://webpass.net/blog/ipv4-exhausted

I (hope to) see CGNAT as the stick - with v6 being the carrot that allows point-to-point apps and personal hosting to work reliably again.

That requires the ISP to offer v6, of course. I'm on Comcast which, say what you will about them, has been years ahead of everyone else for carrier-grade v6 support.

Each /8 only gives us about a month of runway. Not worth the bother.