Why should there be a different standard at home plate than at second and third? People normally find plays at the plate exciting regardless of a collision or not, because there's a run a stake. Home plate collisions are actually kind of random when you think about the nature of the game, it really doesn't fit. There's no reason to risk injuries at this point.
For people who whine about it pussifying the sport, get real, baseball is a pussy sport. Just look at the amount of physical contact in basketball, hockey, soccer, and football, and baseball can't even compare, so why try? It's different, and that's okay.