Copyleft emerged to protect the rights of users of the software against proprietary
software shackles. Proprietary software is focused on making money first, while copylefted
free software such as the GNU project focuses on the user's rights to freely use,
modify, redistribute the software and funding is a secondary question. The objectives of
Copyleft and Proprietary licensing could not be further from each other; So trying to mix
Copyleft with proprietary is not supported by either strategies. I too fail to see the
policy end goal behind copyleft-next. It seems more like the product of experimenting with
licensing ideas just because it's cool.