Earlier quoted context omitted.
That is the liberal perspective, but one radical perspective would be that unfree software causes significant harm to society as a whole despite individuals having the choice not to use it directly, and so should not exist. Note that radicals don't necessarily support passing laws to get what they want - the goal of most political radicalism is to cause a change in society, not to force society at gunpoint to do some…
One can also see harm that the free software movement causes. RMS tried to prevent emacs from having code completion through clang, modularity in gcc and puts software following his definition of freedom before the software being able to fulfill its task in a good way.
One could argue that a society in which people cared about free software would not require the free software movement to attempt to protect itself in such a manner, though. You can find many similar examples in other movements where the movement needs to protect itself from integration into the status quo without completing its goals.