I think he knows what you mean, he's just making a point about the irritating habit of using "digital" as a synonym for downloads and streaming and- even more irritatingly- implying that CDs and DVDs somehow aren't "digital". (Compact Discs were originally marketed using the fact they were digital- it was arguably the biggest selling point, and is even included in the bloody logo!).
I've commented before that I'd expect this kind of annoying use of language in the mainstream press but that you'd expect better from Slashdot which is- or was- a site for genuine geeks interested in the underlying science and technology and not just the superficial "boys toys" aspects (#), but apparently not.
(#) It's my belief that despite the fact people are apparently *much* more tech-savvy than they were even 15 years ago, people's understanding of (and interest in) the underlying fundamentals- such as what "digital" actually means- isn't actually that much better when it comes down to it. Yeah, every man and his dog is obsessed with his smartphone in a way that only marginalised geeks were with technology back in the day- but while they know how to use the Android interface, do they actually understand even at a basic level how the underlying technology (e.g. the Internet and computers) work? They know how many gigabytes is a decent amount for what they want to use, but do they understand what a gigabyte- or rather a byte- actually is? I suspect most people don't. Anyway, as I said, I expect that from the mainstream media, I expect better from Slashdot contributors... except I don't any more. :-(