So I googled "This is Us" and this shows at the top:

Tragedy is a dramatic category, like comedy. In a tragedy, the protagonist, like Hamlet, is put in a situation that is literally impossible to overcome—and then we marvel, and are inspired by, how CLOSE s/he comes to achieving the goal.

I have followed postings about this show because I know that nothing this popular can be worth a damn. This is certainly melodrama. Tragedy is reserved for artists. This is the best province of insurance salespeople.

Tragedy must be something new. It should be a drama. Calling a TV series or especially a movie a tragedy can give away an ending.