I think he has a point, although it's more about the semantics of the term 'information' density.
Shannon information is always measured relative to a receiving context in which it the symbols are understood, and information content is related to the inverse of the probability of observing a particular signal as assessed by the receiver. So from that perspective vinceguidry has a reasonable point.
However really the question being asked is something more like 'data density' and that is generally what people are talking about when the term 'information density' is invoked.
Edit: I see that the original article does indeed refer to Data Density, and that HN title is just wrong.
Shannon information is always measured relative to a receiving context in which it the symbols are understood, and information content is related to the inverse of the probability of observing a particular signal as assessed by the receiver. So from that perspective vinceguidry has a reasonable point.
However really the question being asked is something more like 'data density' and that is generally what people are talking about when the term 'information density' is invoked.
Edit: I see that the original article does indeed refer to Data Density, and that HN title is just wrong.