While "quantum leap" has a specific scientific meaning, that only sort of means something small. It means changing energy levels. For electrons, that takes a very specific -- and small, as everything on that scale is small -- amount of energy.
But metaphorically, it doesn't have to mean something small at all. It doesn't in the eponymous TV series. And it has been used since 1970 in that metaphorical sense. Before that, it was "quantum jump", whose metaphorical usage dates to the 1950s.
Now, overusing the phrase over and over in a single paper, story, documentary, etc. may be annoying. But it's not really incorrect any more than most metaphorical usages of originally-scientific words are.