I think you're being unfair to the audience. The main complaints here aren't about the consequences of those legacy problems, they're about the fact that IPv6 is just such a mediocre designed-by-committee protocol.
Your point about mobile networks kind of illustrates this. There are all sorts of weird and wonderful protocols used in the mobile world, and it doesn't matter because 99.999% of us never have to deal with it, and the 0.001% that do have time and space to become experts. IPv6 isn't like that -- it needs to be a consumer grade protocol that people can understand and work with. It either fails that test, or perhaps at best scrapes a borderline pass. We deserved better.
Your point about mobile networks kind of illustrates this. There are all sorts of weird and wonderful protocols used in the mobile world, and it doesn't matter because 99.999% of us never have to deal with it, and the 0.001% that do have time and space to become experts. IPv6 isn't like that -- it needs to be a consumer grade protocol that people can understand and work with. It either fails that test, or perhaps at best scrapes a borderline pass. We deserved better.