This kind of thing is old hat. It comes up from time to time. rms has written about it a couple of times.

https://www.gnu.org/licenses/hessla.html

https://www.gnu.org/philosophy/programs-must-not-limit-freed...

His basic argument is that it would achieve nothing because such restrictions based on copyright law are likely unenforcible. It just makes the software pointlessly non-free.