I know why waste money on DSL(which money spent on DSL is imho) When wimax can do WAY better UL speeds than DSL and about on par with ULs I have seen from TW.
100/50 is being worked on for mobile wimax, and 1000/? for fixed. Thats better than docsis3.
AND wimax can be used to make a wireless last mile. And from what I hear can congestion can be fixed more easily than cable.