I try not to have SpongeBob bias when it comes to this poll but really: Even discounting SpongeBob, the early-to-mid 2000s were my favorite era. While I do like some of the shows the decade before like Hey Arnold or Rocko, I feel more connected to stuff like Jimmy Neutron, Fairly Oddparents, Avatar, and Danny Phantom.
Hell, the 2000s gave us Nicktoons Network and during its best era in the mid-2000s, we got stuff like Kappa Mikey and The Secret Show so I'd be lying if I said I liked any other decade of Nick more than this one.