The story arcs hit hard because it’s depressing subject matter, but it’s by no means any more real than something happy. You can have friends who support you, a family that loves you, and advancement to medicine have saved many lives especially to those who got immediate care.
Reality is full of hardship, of heartbreak, of tragedy, of death, and many more horrible things. But to say that is only reality is entirely pessimistic. People can be happy and things can work out, that’s the coin we flip in life.
Back to the story; each arc was tragic in that despite working to achieve something it falls flat or worse. Then there’s this happy ending, a moment where they are happy. Of course they will face more hardship, but the story ends in this moment. If you truly believe that life is sad, tragic, and meaningless, then I have something to tell you.