It looks like the setup they want will be pretty crap for home users if that got implemented by ISPs.
You won't be able to tether if ISPs / Mobile networks decide to use the DHCP to give you a single IP.
This stance of Google's benefits consumers. Howv many consumers are there of mobile phones and broadband are there in the world compared to workers in a corporate LAN?
I feel like the question that needs to be asked sometimes is:
Will this enterprise feature negatively affect normal home users.
Imagine your mobile phone network gave you 1 IPv6 address rather than a subnet.
That is bad. But Google standing firm on not implementing the ability to do so, has meant that they gotta implement prefix delegation.