This feels ironically similar to saying Obama failed because he didn't fix Bush's mess fast enough. Nokia was heading for a slow decline. Elop's strategy accelerated that decline short term in hopes they could turn around. It's a risk he and the board fully knew existed. It hasn't gone the way they want fast enough, which sucks, but they had the guts to give it a shot.
Android would have been the safe bet. I don't think any can argue that Nokia would be a much more valuable company today if they took on Samsung for Android leadership instead of going down an empty road with Windows Phone.
Instead, they swung for the fences with WP7. They missed. But, they have a few more chances to try to make it happen, and they're now effectively bankrolled by a company with much deeper pockets and motivation to win then if they stuck with Meego or Symbian.
I can't say I'm confident, but I am optimistic. I wouldn't count them out yet.