RMS' personal choices are important. I could not live with the same ethical purity myself when it comes to software choices (or for that matter, much of anything else). But I have been personally influenced by reading his essays on ethical topics. If he did not live consistent with his personal ethics, not only would he be much less persuasive, but also he would be at conflict with himself.

the critic is right that software freedom does not exist in a vacuum. However, it does not follow that living in an ethical manner is pointless.