I disagree. Reading lecture (! not literature or study books) I read 15 books each weekend in my teens, reading all science fiction and fantasy books in the town's library. And no, not all where 1000 pages long. But they weren't all shorter then 300. And yes, I regurarly went back during the week to catch an extra book or two.

I realize I might be a relatively fast reader, and this fast reading I only did in English (while my mother tongue is Dutch), but do not underestimate how quick some people can read?

I suppose I can concur in your 'low complexity' argument: I did not read Tolkien in my teens, and probably would have skipped all the poetry while reading.

Edit: Clarification: 15 books each weekend should be read as ==>> I traded my 15 books for 15 new books each weekend, reading them during the weekend and when not in school

Again, this isn't a measuring contest but I will point out that you could read that much given you wanted to. Life is tradeoffs after all.