It's harder to prove consumer harm with something as abstract as IP addresses, and there's a bunch of other pieces that make this much less unlikely, such as the fact that USBs already become obsolete and need to be replaced, so you're just shifting the replacement cycle.

With all those addresses locked up at the hyperscalers IPv4 has become anticompetitive. So yes, the EU can prove consumer harm.

They don’t need to prove consumer harm to pass laws.

exactly. US anti-trust requires you prove harm to the consumer. In the EU, anti-competitive behavior is enough.

Actually the US gov’t adopted a policy last November to migrate all services to ipv6 by 2025. So the USA might have some weight in the migration.

https://www.ferc.gov/internet-protocol-version-6-ipv6-policy