The code's meant to be of use educationally and the license is meant to limit it to that purpose. There is not some kind of bait-and-switch here, the fact that the code accompanies a fifty page academic paper is a pretty big hint as to what is going on.
The ironic thing about your comments is that half the open source projects out there would reject the code anyhow if it was GPLed. I'm not sure why we should expect the author of such a paper to pick the magic combination of licenses (because you'd have to have multiple licenses, and that's a pain in the butt) to make everyone happy, when making everyone happy is not the purpose, writing an academic paper is.
Sometimes the value you're going to get from code comes simply from reading it or using it as a reference, and that is okay.
> I.e. this "contribution" would only be relevant if was usable under a really free license, e.g. one of: https://www.gnu.org/licenses/license-list.html#SoftwareLicen....
The ironic thing about your comments is that half the open source projects out there would reject the code anyhow if it was GPLed. I'm not sure why we should expect the author of such a paper to pick the magic combination of licenses (because you'd have to have multiple licenses, and that's a pain in the butt) to make everyone happy, when making everyone happy is not the purpose, writing an academic paper is.
Sometimes the value you're going to get from code comes simply from reading it or using it as a reference, and that is okay.