Ruby was eager to claim that title for herself, and she was even exposing herself to gravitonium in the hopes of gaining unparalleled powers.
Since the return to the present, however, S.H.I.E.L.D. has toyed with the idea that somebody else might be the actual Destroyer of Worlds.
Agents of S.H.I.E.L.D. kicked off Season 5 with the world destroyed, and the story at first was that Daisy had quaked the planet apart with her powers.
In the future, she was known as the Destroyer of Worlds.