I wouldn't call 10 years a "sharp" turn or a "fickle" change. I'd call it stubbornly gradual.
If this was just about the money it would have made much more sense to do this on TV or OVA. And any network would have certainly jumped at a chance, if not begged and pleaded, to have the new EVA show to air.
To further explore why Anno's sentiments may have changed from "it's over and I'm done with it" 10 years ago to what it appears to be today, let's take a look at what has happened in the animation world in the time since End of Eva was released in the summer of 1997:
- Anime has made huge strides outside of Japan. In the west it's gone from underground showings at college campuses to mainstream theaters and TV. American and European companies are making co-productions with Japanese studios. And American and European cartoons have even started to take on a distinctly Japanese look. Basically, there's a MUCH bigger audience for Eva today, one that was never there in 1997.
- The Internet has changed the lanRABcape of television and movies in general. The web had already taken off back then, but it was nothing like it is today. There was no YouTube, no MySpace, no bittorrent, etc. Everybody can basically see everything now. Audiences are far more jaded today - they think they've seen everything, and it's far more difficult for filmmakers to create something that truly challenges people's perspectives. And that's what Eva was really all about, changing conventional perspectives.
- Countless new animes have been produced (see my comment above about Pokemon), but to date there's been nothing that comes even close to challenging viewers the way Eva did. I'm NOT saying there's been nothing as good or better than Eva, but nothing has come out that has truly challenged its audiences to the same degree.
I think this is what Anno meant when he made that bold statement that was something like "No anime has been released that is 'as new' and Evangelion". He was directing that at the industry and other animators as much as he was audiences. Maybe what he hopes to do is to make people remeraber how much Eva shook things up all by itself, and hopefully it will be a wake-up call to a new generation of artists and audiences alike to demand and create more stuff that will both excite and enrage the way Evangelion did.