[zozbot234]

This is an ongoing, large-scale project, so I'm not sure that it comes with any expectations of openness. They're not placing extra limitations on something that could easily be open (which is quite tiresome), they're doing something new.

[tokai]

Who said anything about expectations of openness? They used a CC license, while at the same time adding further restrictions. They could just have claimed full and proper copyright, instead of this impossible misunderstanding that they ended up with.