The counterargument, maybe their license doesn't block us from using their work in the way they think it does, and until it's proven in court we won't know is extremely offensive and self-serving.
This is the same argument raised by many GPL violators. "The GPL hasn't been proven well enough in court in my jurisdiction so I'm just going to use your code in violation of your license terms."
This is theft, an open source license violation, and lawyering to defend that theft. It violates the principles of open source. We are literally discussing an OSI approved license. I believe that any responsible member of the open source community would respect the authors license and not try to lawyer their license out of your way so you can have their code on your terms.
If this was Linux devs and GPL, rather than Solaris devs and CDDL, everyone would be on the other side of this argument. It's hypocrisy and it should be called out.