> The current problem with IPv6 adoption is that nobody has yet said "let's stop processing IPv4 traffic"…

One of the giant CDNs translates all IPv4 traffic to IPv6 at the edge (stateless NAT46) and is IPv6-only in its core network (for one of its primary product networks; like everybody they have multiple networks.)

Multiple networks do the same - Both T-Mobile (at least in EU) and Orange no longer actually support v4 other than through funky 464 and by funky I mean really funky at times.