> ...and didn't where it doesn't matter yet.

Given the number of scaredy-ass ISPs out there who refuse to offer IPv6 service, I disagree with this. But I do strongly agree with the rest of your comment.

I also very strongly assert that claims of the form "IPv6 is not the only version of IP used on the Internet, therefor it is a complete failure." maybe with a side of "And this 'failure' means that IPv6 is a dead protocol." are just plain stupid. v4 and v6 were very deliberately designed to coexist, and if v4 continues to run on the Internet until the day the Internet is shut down, that's totally fine.

In my opinion, the most plausible future is one I mention in my second paragraph here. [0]

[0] <https://news.ycombinator.com/item?id=50297244>