Earlier quoted context omitted.
Not "from scratch" but there are tons of routers that either don't support IPv6 or have broken support and thus need to be replaced.
>Not "from scratch" but there are tons of routers that either don't support IPv6 or have broken support and thus need to be replaced. A fair point. Many older (and possibly some current) consumer routers don't support IPv6 and would obviously need to be replaced. That said, AFAICT, all the Tier I and Tier II providers and most major ISPs routing infrastructures support IPv6. Depressingly, many of those don't offer IP…
There's something they have to change to turn on IPv6 for your area, whether it's swapping a CMTS or updating an IPAM database or whatever, and that change costs both time and money so Spectrum is gradually rolling it out across the network. The cost of the migration is so large that it has to be spread over a decade or more so the shareholders don't revolt. It's frustrating but it's not evil (if they truly hated IPv6 they'd just never support it at all).