As long as the people don't change too drastically I doubt they will have much trouble. Its like looking at the Mona Lisa and being like "This is fucking great, but da Vinci really screwed himself ay, he's in a lose lose situation now so his next painting has to be shit because he can't live up to hype".
News flash that's not how art works. ND has become masters of the craft and what they have been making, like it or not is art. Sure not everyone will get it or like it but that doesn't matter. Fact is they make games they like and enjoy, and so far they have shown they have good taste. They aren't like some devs that constantly rotate people in order to save money. They have a clear vision and strong leadership and dedicated teams. Which can't be said about other devs. Quality usually turns to shit when you constantly replace people or change devs completely like with Halo for example.
Luckily ND isn't doing that, so as long as they stay true to themselves, make games that they enjoy, and keep up with technology they will be fine.