[eppp]

That is one of the most disappointing aspects of ipv6. Even if you implement it perfectly you are still stuck with having to deal with ipv4 with no end in sight. Had backward compatibility been a primary goal, is there any doubt we would have made vastly more progress at this point 20+ years later?

[azernik]

It's an address space expansion. You were always going to need hacky stuff for legacy clients, and for any service that wants to be reachable by said clients.

[tialaramex]

> It's an address space expansion

Exactly this. There is no "backwards compatible" way to have more addresses in a protocol that's wedded to 32-bit addresses. That's just how numbers work. The protocol with a larger address space will be incompatible, and so anybody who seems surprised/ disappointed hasn't even really thought about the problem.