Sorry, but you're just plain wrong.
A book is a piece of long form text, and that's what maflynn was referring to when he decried hexonxonx's rejection of them. hexonxonx referred to 'books these days, paper, digital or otherwise' - so digital (e) books were definitely within the context of their discussion.
If by 'basic definition' you're referring to a dictionary such as Marriam Webster - then the electronic long form text that maflynn was referring to is satisfied by
definitions 1c and 1d. In addition, the definition specifically includes 1g - eBook. You are factually incorrect by reference to this 'basic definition'.