That is true for the data lookup part where DHTs are replacing DNS in a way put still the peers need to discover each other's ip in some way.

I don't know what would be the term for it since it is not completely centralised, as in the nodes collectively form the system without any central coordination, but a new node joining in still needs some information to connect to the network from some source which could be denied-of-service by say a government, so not completely decentralised either.