What really irks me is quibbling about headlines that are technically inaccurate, but are actually just common everyday usage that everyone understands perfectly well not to take literally. Comments like that have deeply negative value and drive me up the wall. In this case though I think I agree with the criticism, in everyday usage "a fraction of" is generally taken to mean quite a small fraction, which this isn't.

Another commenter is applying the literal definition of fraction to argue the title is accurate, and quite rightly getting downvoted into oblivion for it. Everybody (who is a native English speaker) knows very well what this phrase is taken to mean in everyday English.