IPv6 failed because they tried to boil the ocean. It was design by committee, where everyone got their pet feature thrown in to appease and gain consensus. Alternatively IPv4 is a mountain of small hacks, which is its biggest strength.
We could have done a lot of good by adopting proposals to extend v4 like 0/8 and class D, but instead the decision was made to collectively drown the babies in the bathwater and insist on v6 at all costs.
We could have done a lot of good by adopting proposals to extend v4 like 0/8 and class D, but instead the decision was made to collectively drown the babies in the bathwater and insist on v6 at all costs.