We've found another problem with IPv6: It's sparked a punch-up between top networks

Peering rows lead to traffic turbulence – report

Analysis  We've discovered another reason why IPv6 is, right now, a poor substitute to IPv4: fisticuffs have broken out over the protocol on the internet's trunk roads, causing traffic jams.…

via The Register - Data Centre: Networks
http://go.theregister.com/feed/www.theregister.co.uk/2018/08/28/ipv6_peering_squabbles/