I think that either the dev has unexpectedly passed away or that he has disappeared for some other reasons unknown. Did he simply give up on the coin and the ICCO announcement was his last ditch effort to pump and dump? It doesn't seem like it because he did a terrible job pumping...it never happened. It also doesn't seem right for such an advanced coin at this age. Why put in all the work? However, thinking back in time there was one fairly large rally that occurred in 2015. Maybe it was a pump and dump? The "XDN Foundation" appeared in May of 2015, held an auction and then XDN price went up a month or two later to ATH's and the XDN Foundation magically disappeared (and most likely sold all their coins at the top). Here's the thread for that: https://bitcointalksearch.org/topic/xdn-foundation-1072773
dNote had always said that the foundation seemed like it was for a good cause but he did clarify that the foundation was not official and he was not connected. Was he actually connected and that was just phase 1 of scam? Tinfoil hat is on...but the truth is we have no idea and it is all speculation. I mean shit...I dont know. Why would he build such awesome technology just to scam poorly? Maybe something unfortunate happened?
Either way the source code is available for us all and for someone to take the reigns if they have the intelligence and vigor...it wouldn't be the first time that a dev for a popular cryptocurrency disappeared before the coin "took off", after all.
Seems kinda likely, imo. After all he always talked about the "team," but he was the only dev of Digitalnote anyone actually knew.
The ICCO seemed dodgy from the start anyway. I doubt he passed away, he's known for disappearing months on end. I bet you that he has more than pone account on this forum anyway.