IPv6 is present in all modern smartphones - it's a requirement of the protocols involved.
IPv6 is present in all modern communication protocols - including DOCSIS.
IPv6 is present in all modern operating systems. It took decades to get it in there.
IPv6 is present in all modern switching/routing hardware. It took decades to get it in there.
Nobody is going to supplant IPv6.
You know what hindered it? That NONSENSE about it meaning that every device had to have a globally addressable address. That was the problem. Nobody wants their local devices to have an address like that. NAT is perfectly fine. And converting a NAT network to IPv6 consists of this... add IPv6 to the gateway device. Done. Everything else can be done at leisure, or stay IPv4 into perpetuity - nobody would ever care.
That nonsense literally held back adoption, because who the hell wants to go through every switch, router, server, client, phone, printer, etc. and give them all IPv6 addresses and then address them only by that? Nobody. Internal networks, it does not matter how they operate. That's why they're internal.
But the anti-NAT brigade set us back 10 years on IPv6 because of that.
You are not going to get anything but IPv6 for the next 20 years. Deal with it. Activating it, using it testing it, and understanding it takes about an hour tops for any IT professional, with a deployment plan then going into normal change management.
Sorry, but you can make all the excuses you like, like The Reg does. All my servers, domains, etc. are IPv6 capable and have been for years. It really doesn't take much and things like log-file analysers and custom-made sticking-plaster scripts are the things that need time to be converted. The protocol support? It's just there. In your device, in your OS, in all the things you use that OS on.
And deploying it affects nothing IPv4-wise, so there's no reason not to. Do it using ipv6.yourdomain.com and say it's a test. Google report that something approaching 10% of their traffic is IPv6 now. It's not going anywhere.