Re: Why didn't they follow the phone system?
No, not joking. Legacy systems are all well and good, but EVERY other industry in the world modernises when new needs arise.
People complain about IPv6 because it requires a complete redesign of their networks. So, a suggestion is to not have to "completely redesign" them, but extend existing concepts - just like every other industry does.
Those downvoting me - what is your suggestion, because as far as I can see there are very few options:
1. Run out of IPv4 addresses - this has pretty much happened
2. Roll out IPv6, and redesign everything to handle it - including those "legacy systems" that people so keenly cry about constantly.
3. Come up with an easier solution that doesn't require a complete redesign of how networks work.
From what I can tell, people here seem to want things all ways - they want IPv4, they want it to be replaced with something that doesn't require work, they don't want to replace legacy systems. Remember, those legacy systems that only support 32 bit addresses won't support IPv6 anyway!
Its basically Brexit, but with IP addresses - you want unicorns.