That's still what I would call a v6-only (with translation mechanisms) client deployment. Sorry for being imprecise on the "with translation mechanisms" part.
> Some absolutely will.
Very few, in my prediction. We're already seeing massive v6 + CG-NAT-only deployments these days, and the NAT part is starting to have worse performance characteristics: Higher latency because the NATs aren't as geographically distributed as the v6 gateway routers, shorter-lived TCP connections because IP/port tuples are adding a tighter resource constraint than connection tracking memory alone etc.
This, and top-down mandates like Apple's "all apps must work on v6 only phones", is pushing most big services to become v6 reachable.
At some point, some ISP is going to decide that v6 only (i.e. without translation mechanisms) Internet is "enough" for their users. Hackers will complain, call it "not real Internet" (and have a point, just like I don't consider NATted v4 "real Internet"!), but most profit-oriented companies will react by quickly providing rudimentary v6 connectivity via assigning a v6 address to their load balancer and setting an AAAA record.
I agree that v4 only servers will stick around for decades, just like there are still many non-Internet networks out there, but v4 only reachability will become a non-starter for anything that humans/eyeballs will want to access. And at some point, the fraction of v4-only eyeballs will become so small that it'll start becoming feasible to serve content on v6 only. At that point, v4 will be finally considered "not the real Internet" too.
