I didn't say anything about exclusively using CDs, DVDs, etc. I'm talking about removing DRM. Amazon et al do not get to unilaterally enforce their notions of ownership. Consumers can take control of the things they buy if they choose to.
The author is talking about a societal shift whose consequences are difficult to foresee; one person electing to [strip DRM from media they purchase in violation of US law] makes little difference to the broader trend.