[Someone]

And that, for instance, means that your simulation running on a huge CPU cluster that does not even have a GPU can run interactive graphics on your desktop GPU.

I am not sure whether that still is a big advantage nowadays, as the typical cluster is fast enough to do OpenGL in software, but 20 years or so ago, this was a big issue, as that huge cluster might have been a 4 CPU, 2 GB, 100 MHz machine, if you were lucky.