You say you couldn't use the software, which is not completely true.
Sorry that I didn't spell out that I meant that I couldn't use it from a business point of view. I assumed that readers would be able to figure that out without me having to explain every detail.
Although many people make money selling GPL'ed software, it just doesn't make sense for many business scenarios, in which case the business "can't use the software" (again, in a practical business sense.)
In my case, the business is a small one that I operate out of my home as a sideline. It sells something extremely specialized in very low volume. It's not lucrative, but it has made enough money over the years to be worth my time.
If I were to incorporate any GPL'ed software into it, I would then need to GPL the whole thing (isn't that the whole idea of the GPL?), and the few sales I have would dry up completely. Since it has such a small user base, I would be unlikely to make any money in any of the common open source revenue models, such as selling media or service.
So let's think about this realistically from a business point of view only, not trying to make the world a better place, like your beloved RMS. (Some of us want to be able to afford to shave, take a bath, and subsist on something tastier than toe jam.) I could incorporate a single function that had been translated from unlicensed Fortran to C and GPL'ed, and then lose my entire small business. Or, I could translate the function from Fortran to C myself, where the unspecified license of the original Fortran would remain unspecified in the new version.
So, which would you do?
Remember, you're not allowed to make the world a better place in this scenario, except by providing proprietary, closed-source software to end users that does a useful, highly specialized function, at a price that many are happy to pay.
BTW, my version of freedom is superior to RMS's because it's freer. Isn't that axiomatic? If freedom with a few restrictions is good, freedom without the restrictions must be better. I've always thought it was a great fraud to describe restrictions as "freedom".