The slow adoption of IPv6 by many older companies is at least in part a paradoxical result of the success of IPv6 elsewhere, particularly in new builds where there is practically no overhead in deploying IPv6 in a green-field environment - see for example the mobile telecoms market in developing countries, where new builds are IPv6-first.

This has taken pressure off the IPv4 legacy address pool, reducing the urgency for older providers.

End-users are typically completely unaware of whether their traffic is being carried over IPv6 or IPv4, and so simply do not care one way or the other. (This particular post is more than likely being made over IPv6, since news.ycombinator.com has an IPv6 address and my OS, browser, router and ISP all support IPv6 straight out of the box, as is now true for the majority of users in my country.)