"Perhaps there is limited support in the UK, but I can tell you quite clearly that the major ISPs in the US support IPv6"
The same applies across Europe.
The UK is seriously laggardly.
OFCOM promised 4 years ago that when IPv6 hit a threshold they would no longer allow ISPs not selling IPv6 to call their product "Internet access", but they wouldn't specify the threshold then and show no sign of applying it now.
It's time that misleading advertising claims were launched.