It's part of human nature. Like all aspects of human nature, it can get perverted or out of balance.
There is, however, a difference between schadenfreude and simple sadism. The latter seems to be on the rise.
There's also the more subtle issue of extreme tribalism, where any loss experienced by one's enemy is considered beneficial for one's own tribe, and thus cause for celebration.
Tribalism has been exacerbated and perverted, and sadistic joy increased as a result.
However, it is *perfectly* acceptable to derive entertainment from another person's *buffering*...
... while they consider new information...
... especially if one has just destroyed the other's world view through the judicious application of an irrefutable fact bomb.
@codinghorror laudable, even as we all enjoy the concept of comeuppance and retribution more than we admit. But I too watch far less television because I do not enjoy the depicted suffering, and hate being told it's supposed to be entertaining.
Much like how the story of Jesus and the woman he saved from stoning is the biggest proof that those who loudly proclaim themselves Christians do not actually follow his teachings.