I would call this person a sadist

In general usage, I believe, a sadist is someone who enjoys inflicting pain, physical or psychological, on someone else.

What might be wanted here is a more generalized, 'innocent' enjoyment of another person's misfortune which celebrities and politicians often complain about when they fall from grace.

Your word "epicaricacy" is a good word, tsuwm, altho a bit of a mouthful. If "epicaricacy" means "taking pleasure in others' misfortune", then someone who takes such pleasure is an "epicaricacist" [which is even more of a mouthful].

Perhaps a new coinage is in order.

Taking inspiration from the word "killjoy" [meaning "party pooper"], how about: "gloomjoy".

Thus, a person who delights in the misfortunes of celebrities (and others) as reported in the news [and often fabricated for their peculiar delectation in gossip magazines] is a "gloomjoy".

Judging from the popularity of gossip magazines like the National Enquirer, I fathom there are a lot more gloomjoys around than there are sadists. That's a good thing ... I guess. [It probably keeps some gloomjoys from evolving into sadists.]