This really is not such a wrong impression. The corset did have its heyday in the nineteenth century. Then, the female figure was forcefully molded a certain way so as to have women fit what was then considered the ideal form.
The corset was not always just a high class women’s accessory. Also, it was not always constructed to give women the hourglass shape for which it is probably most famous for.
Even in the nineteenth century men wore them to accentuate their shape to fit the current fashion. What was considered to be an ideal shape for men and women varied from decade to decade. The idea of the hourglass figure–large chest, thin waist, big hips–was only popular for a short while; though, it did come back as a trend from time to time. For some periods the corset was used to give women the illusion of having a perfectly straight figure. In these cases the chest was diminished until the wearer appeared somewhat tubular.
As the fashions changed, so did the corset. The way they were worn and their size and shape changed as well. In the 1920s, they had their longest absence from fashion, not coming back until a brief period in the mid century.
These days the corset is still around but few people wear it for its originally intended purpose; make no mistake, though, the corset has never gone away.