Caporegime
I suppose the other way of looking at it is how many champions have been forgotten or will be forgotten? How many could name the year Denny Hulme was champion unless they looked it up (or played Grand Prix Legends)? What about Phil Hill? Damon Hill or Nico Rosberg might only be remembered as sons of champions in another 50+ years rather than for their characters or on-track accomplishments.
I guess there's a distinction to be made between mere champions and true greats: Nico, Keke, the Hills, etc. are not going to make many people's lists of greatest F1 drivers ever. Moss, on the other hand, is going to make a lot of such lists despite never winning. I guess there's always a dilution effect as well, Moss might not be remembered as well if he'd not been one of the greats in the early days of the sport. Nigel and Damon were household names in my youth, but they're already fading from memory.
Seeing how another nationality views these guys is also interesting: Nico is a much bigger star here than in the UK, and the Schumacher name is something else here: Formula 3 commentary here basically gives you blow by blow coverage of David Schumacher racing some other dudes.
You're not going to tell me that they're all forgotten
To be honest, I'd more forgotten that they didn't win the WDC.