Why is "diving" in hockey always called with a penalty on the other team? Why isn't "diving" called alone?

Because it usually still is a trip/slash, but it's incredibly embellished by the other player, thus both get penalties

Players don't just dive arbitrarily. They experience a penalty against them but act like it's worse than it is to try to fool the refs, players, and fans. Embellishment is unsportsmanlike and therefore a penalty.

It's called that way frequently, in my experience. But Semin's right. Somehow. You're right, that's exactly what should (and does) happen.

It's frustrating, but usually there is some minor infraction. Like getting your stick up high on someone and they go down like a ton of bricks. They dive when they know the other guy is doing something wrong that the refs won't notice. Occasionally there are just diving calls, but usually they are coincidental minors. I think diving is an epidemic in the NHL right now. Especially from the Canucks. It's clearly a part of their strategy. They are not alone. I'm not sure how you solve it.