Well, it's just an opinion of an adviser, for now. The actual court decision hasn't been announced.

Not sure. What I read is "source code is not protected by copyright but algorithms can and should be protected", which would actually make licenses like GPL useless and software patents enforceable. Or did I miss something?

You misread. The ability to do something is not covered by copyright (in this case, the ability of a program to implement the SAS language), while "the means for achieving these functionalities may be protected by copyright."

So you can copyright source code itself, but not the algo or functionality produced by that code. Right?

That's what patents do.

*in the US

Thanks for the clarification. The other entry on HN has IMHO much better wording, and goes more in depth.