Google seemingly does this a lot (although I don't know if it's included in their transparency report or if anyone has tried to measure it -- both of which would be nice). You can report predictions as "inappropriate" (look at the lower right of a prediction list in a desktop browser) and you'll see something like

  Which predictions were inappropriate?
  [...]

  The predictions selected above are:
  Irrelevant
  Violence or gore
  Sexually explicit, vulgar, or profane
  Hateful against groups
  Sensitive or disparaging for individuals
  Dangerous or harmful activity
  Other

If Google agrees with the complaint, the prediction could be removed regardless of the popularity of the underlying search.