No, the author's idea is ok and he's mostly right on the cost part. Configuration and the numbers are a bit off and unrealistic, you won't get such low 95% availability per site due to other economical and technological constraints, you'll get at least 99%, but probably closer to three nines per site and 64 out of 96 won't be necessary at all (something like 8 out of 12 could be enough). Dropbox designer is just ignorant, biased and conditioned to US market and environment, but appeals to authority, so people upvote his bad comment. I do storage too, on smaller scale than Dropbox of course, not in the US, but it is distributed and the cost is already lower than what you see in the title.