Alan Held is a very talented guy, but the ROH will want to have someone well-established in the role of Wotan for a cycle, since it's the central character and the crux of the production... most aspiring Wotans will normally sing the role in a smaller theatre first, and go off to Dortmund or Nurnberg or Tokyo etc. (The same applies to Brunnhildes and Siegfrieds, although Domingo's probably entitled to a rain-check on that one
For example British soprano Susan Bullock is "working-up" Brunnhilde, and has done two Rings in smaller houses, notably in Tokyo).
Meantime, by way of illustrating the problem of "celebrity" and why people want "names they've heard of", here are some remarks extracted from "Have Your Say" on the BBC News website, in relation to Pavarotti's passing:
I can't say I've heard much of Pavarotti's work or of his singing, but he is still probably the most famous singer I've heard of.
I'm not a fan of Opera but Pavarotti was one of a kind and will not be forgotten.
I wasn't a fan of opera, but was very sad to hear of Luciano's death. He always seemed like a nice person too. I will always remember him for Nessum Dorma in the 1990 World Cup - an anthem that still lives on and stirs up so many emotions. RIP Pavarotti.
I am not suggesting they're not entitled to their opinion, and it's great they register some sadness on his leaving us.