the SD-DZ failed because on launch it was simply bad, and expensive. The CDJ simply worked well all the time. the Technics had the master-tempo issue for example which was really dumb.
I think the 2000 nexus is a logical and good evolution of the CDJ 2000. the sync button is only normal. the CDJ 2K already shows BPMs down to a decimal.
But I do feel its a bit too much aimed at super-PRO DJs, the big names. The average working DJ doesn't need half the functions because in a small club you'd have 2, maybe 3 of these players. Also you wouldn't be preparing your tracks on your phone because you are in your private jet. You'd be at home in front of your computer, then take the bus to the club.
Technics SL1210mk2s and a Freevox DJ CLUB