Here's a thought. Industry leading bodies* should announce that from 2026 all internet connections sold in the UK will be IPv6 only, and thus all CPEs must support IPv6 on the WAN and the LAN side, with no IPv4 on either. ISPs can then offer a DNS64/NAT64 service for customers, particularly consumers, who can't implement their own solution.
I think that allowing the current situation to drag out simply causes more pain in the long run, and we all know that when there's no real deadline nothing ever finishes! * the LINX, LONAP, MANAP etc, UKNOF and the biggest ISPs such as BT and Sky. I can't include Virgin, Talktalk and PlusNet since they seem to be somewhat silent on this ;-)