It's not a new thing, but it was usually reserved for fights where it made sense. Nowadays though it seems like we do it for every dang fight, even the ones it doesn't make sense for, and the overuse kinda kills the impact of it.

Being sad because you killed a sin eater/lightwarden makes sense, considering their origins.

Beating up a haywire robot in the Twinning isn't a sad event, I should be happy for doing so and at least nod, even if I'm not full on /cheer-ing.