> You did exactly that.

You may want to reread my original post carefully.

> I truly hope that you are wrong and Stallman does not believe proprietary software to be an evil on par with slavery.

I can't claim to know the internal ranking of evil things in Stallman's mind, but nonfree software is very clearly beyond the line of unjustifiable evil for him.

"While we can distinguish various nonfree distribution schemes in terms of how far they fall short of being free, we consider them all equally unethical.", from https://www.gnu.org/philosophy/free-sw.en.html