I didn't interpret the article that way at all -- I can understand how somebody saying "hey, look at these neat things I found and learned outside!" could be misinterpreted as "self-important wankery" due to the natural "great for you!" or "who gives a shit?" reactions that kind of thing tends to garner. I at least found it neat _because of_ (not in spite of) the feeling that it was almost as if I was reading from the author's personal diary.
Why such a negative reaction? I legitimately don't get your hostility. Imagine if a kindergartener wrote a book about their day spent playing outside on a Saturday -- would you call that "self-important wankery", too?