As you noted John, its the plethora of software, support systems, tooling, and most important in many environments - legacy customer management and provisioning systems that can be the limiting factor. ...
Just looking around my office, I have a Cisco SPA112 two-port ATA. It's been discontinued but Cisco says they will support it through 2025 and they shipped a firmware update in 2019. It works fine on IPv4 behind a NAT. It has no v6 support at all and never will. Multiply that by a zillion and you can see that IPv4 isn't going away any time soon.
Regards, John Levine, jo...@taugh.com, Primary Perpetrator of "The Internet for Dummies", Please consider the environment before reading this e-mail. https://jl.ly
