Every now and then, a crime of such magnitude happens (the woman was assaulted to such an extent that her internal organs were damaged from iron rods inserted into her vagina, which speaks to more of cruelty and inhumanity, than the need for sexual gratification) that it captures the news cycle. This is the reason the case was quickly solved (quickly as in about 5 years)

But there are many rapes, that are not reported, or if reported, the victim seldom gets justice because of dragging in courts, etc.

And, in any judicial system, solid evidence is required, so rape of a woman in a field, at night, where she might not even remember the faces of her assaulters, might not have enough evidence, apart from circumstantial ones (in cases where the assaulters escaped), leading to no justice to her.