A familiar unfair comment on IPv6 is that people have been calling for its adoption for almost 20 years but the Internet did not collapse, therefore they imply we can continue to put it on the long finger. This ignores that no one did very much for most of those years to make it happen because of human nature and the fact that the IPv4 addresses only ran at the global allocation level in 2011.
The encouraging thing is that IPv6 adoption got going in 2011 and has continued to grow year after year since. Equipment vendors began to support it in their equipment and the support gets better every year. The companies that might be expected to be first to deploy it are (notable exception being Amazon). It will just keep growing from here until a point is reached when people care more if their IPv6 goes down.