> Announced by who? The United World Government?
Yes, also known as the US government, because that's where those services are located, and who ultimately controls 99% of the Internet through .com/.net/.org.
"Domains with more than (some definition of "big") under .com/.net/.org must not point to nameservers announcing A records for any of the subdomains. DNS server operators serving more than X clients must report aggregate statistics."
Is it practical? Realistic? A good idea? Probably neither. But it would be a feasible way to ensure IPv6 support, with worldwide effects.
> Now it’s ISPs, in your previous comment is was websites.
The government forces website operators to offer only IPv6. As a result, ISPs that don't support IPv6 are about as useful as a provider that drops a wet string at your doorstep. Thus, in order to be useful and deliver a service worth paying for to your customers, ISPs would be forced to support IPv6, even without a legal mandate.
Due to the dominance of US web services, the US doing this would force this upon ISPs worldwide.
> you have to replace all end user devices
In most cases, not the devices, only the software, or rather, the configuration on it.
> container ships’ worth of PS5s
The PS4 and 5 support IPv6 according to what I found. https://toreanderson.github.io/2021/02/23/ipv6-support-in-th...
Most importantly, in the proposed model, Sony would most likely fall under "larger than X" if services were included, i.e. they'd have to switch to IPv6-only too (and issue updates to support that or leave their users stranded).
Maybe add an exemption for services supporting systems last sold more than X years ago.