I think a lot of the image problems cockers have come from the fact that they have all these scary looking bits hanging off it all over the place, and ther back block rattling away in your face. Add to that the reputation it gaind in the mech days when people who didnt know what they were doing tinkered and broke them, and the two-stage trigger that you had to get used to, and you can understand why people don't like them.
Personally, in the 4 and a half years of owning my Evo, the only time I did any adjustments to the timing was when I put my race frame on, in the 2 and a half years it was a mech it wasn't re-timed once, because it wasn't fiddled with.
If I were to open up a matrix, or an angel, or whatever, and fiddle with the buttons and switches, and mess around with the LPRs and whatnot, would you expect it to work straight from your bag? Me neither.
Personally, I think that with the mid-block mini-revolution that is going on right now, with Raceguns Halfblock, Docs Fastback, the Turtle, the Catapult et al, and new developments such as the mQ-valve, there is at least another 4 or 5 years left in the life of the autococker as a top level marker.
As for Nexus moving away from their cockers, unfortunately most of us can only ever speculate on the sponsorship deals that top teams have, and how much of that is free choice, and how much is Planet wanting to promote thier new baby.
[edit - need to type quicker, Silky and Skeet posted while I was typing this]