If you came here looking for a big juicy scandalous reason for the demise of the NEDA organization, then you will be disappointed. NEDA is history for the same reason that many clubs fail. A lack of people who are willing and able to take over the work of the club when the old timers get tired and burnt out.
Packet networking on a wide scale never did have the support of a large user base.
Users generally used but did not contribute either funds or their time to building the network. In most cases they wanted fast networks for nothing. When the internet got fast, they went off in search of more glitz and whistles. Early in 1999, at the last directors meeting held, we even had trouble getting enough people willing to form a quorum. It was time to close down.