To be honest, I think anyone who thought this would 'kill' Pokemon were just being delusional or didn't know enough about these games. It's true that they sold like hotcakes in Japan, kids were eating it up, the anime was doing really well, etc. But that's what happens for almost all Level 5 franchises geared towards kids.
I don't know what it is, they have some sort of magic touch. But at the same time, they over-saturate the market with it and it almost always dies out after a few years. Don't know why people thought it would be different this time.
