Copyright is what allows people to "control code." Copyleft is necessary to in essence "reverse the effects" of copyright. So yes it does technically leverage the control copyright provides, but this is necessary as everything is copyrighted by default. The author being able to re-license code he owns the copyrights to is an unfortunate side effect of copyright, but there is little that copyleft can do about that, it could happen regardless of the license chosen. A possible solution would be to transfer copyright to a group or person you know will never license anything under a proprietary license, such as the FSF.
Please refrain from using non-sequiturs like "communistic" to describe things. Copyleft does not deny anyone the ability to exercise any freedom including selling the software. The idea of copyright, and the idea that software should have "owners" are non-capitalistic ideas to begin with, so if anything the proprietary software companies are practicing authoritarianism.
Please refrain from using non-sequiturs like "communistic" to describe things. Copyleft does not deny anyone the ability to exercise any freedom including selling the software. The idea of copyright, and the idea that software should have "owners" are non-capitalistic ideas to begin with, so if anything the proprietary software companies are practicing authoritarianism.