That's a ridiculous statistic purely contrived for a sensational headline. If you want to a more reasonable measure than you should count the number of sites where users are giving personally identifiable information. Those are the sites where policies should be read and that will be a much smaller number.
Given that, I do think privacy policies can be more concise, but that likely won't happen with out some sort of tort reform. Policies are long because businesses need to cover all of their bases in a litigious society.
IP addresses are circumstantial evidence for identifying a person (particularly when combined with timing and correlated with other sites, as is easy for large ad and social networks to do); it's somewhat difficult to use the web without disclosing your IP.
(Also, I feel obliged to point out your interest in this matter. You work for IAPP, which, as far as I can make out, is an association of people on the corporate side of privacy compliance.)
Do you read all the privacy statements of sites that you give personal information to? Every site gets at least your IP address, which has been used in courts to identify people (albeit in a flawed and usually incorrect way). There is a vast amount of information that each of us gives away every time they are on the internet. What we read, what we buy, what interests us, who we talk to, what we say, where we are and much more can be gathered by websites. What sites and companies do with this information varies. Legal contexts vary state to state, nation to nation (some are completely laissez-faire to very protective of users).
The article makes an accurate point about privacy being almost incomprehensible and near impossible to fully understand because of the depth and volume of privacy statements. The article's point is backed up with numbers. How can it be reasonable when the quantity of reading required to have a basic understanding of what sites say they won't do with your information is "too much"?
Given that, I do think privacy policies can be more concise, but that likely won't happen with out some sort of tort reform. Policies are long because businesses need to cover all of their bases in a litigious society.