You are reading too much into it. I (and probably the person you replied to) have nothing against long-form articles, as a matter of fact I prefer them.
On a typical day, I will spend 1-2 hours on a book, I will read many smaller articles here on HN and on Reddit, I will also check out my RSS reader, I will read work-related email, I will do actual work, I will train for my marathon (alternate day running and weights) which takes about 2 hours, spend time with my family, socialize, and hopefully get some sleep too. Its all about how you manage your time, not about distilling long-forms into bite-size chunks.
If given a choice between reading a long-form article online or reading a book, I will read a book.
There is only so much time in a day. There is so much to do. I save long article like this for my lazy or slow days to read.