Let's use IPv6 more and it'll worth far less than $2B.
The problem with IPv6 is that it's a fundamentally flawed design. Which looks easier to input / dictate over the phone / write down somewhere? 220.12.30.01 or 2001:cdba:0000:0000:0000:0000:3257:9652?
I've been in networking for 30 years, worked for multiple multinational ISPs, and the answer is basically never.