I would say that since the stone was part of the ring, it became part of what effected the curse. Not to read too far into canon, but perhaps the destruction/separation of stone and ring may have actually triggered the curse, much the way that holding an object during the killing curse fractures a portion of the soul into the object...which could almost be seen as a type of curse as well. At any rate, the construct of the article has some decent consistency with a pretty big storyline theme - our attempts to become invincible or immortal typically aren't going to pan out. From Beedle the Bard we learned that the elder wand, presumed to make its owner pretty unbeatable, usually changed owners through violent means. The Sorcerers/Philosophers stone created by Flamel was unable to be acquired by one who wished to use it. There always seems to be a thread of the under-assuming, the underdog, beating the odds against those who would seek to dominate all. Thats definitely not a new premise to many great stories. Dumbledore didn't want the stone, and didn't really have much need for the hallows post-curse. He knew Harry had the cloak, he most likely ed it on to him that 1st Christmas at Hogwarts, even then he may have reached a conclusion that the pursuit wasn't a worthy one. Of course, the movie makers really erred having Harry break the wand, at least in of a reuniting effort for more movies down the road. They could have him swap the wand out for a fake that he broke in front of Rob and Hermione so they could trurhfully say they saw him break it to anyone that asks. That would take the target off him or them versus future power seekers. Then, picture it, some time later, the 'swap out' scene is shown and we the viewer realize that the elder wand lives after all! And then who knows, a trilogy or 4 later, they could be reunited, and the storyline continues against the newest bad guy.