Read-it-straight-through, all-text books won't vanish, of course. But having a taste for spending a lot of time with them may very well come to be seen as a rather special, even odd, thing, like the taste for reading poetry or going to the ballet is today.
The 2Blowhards also point out that writers are dingalings, that the real creative people are the editors and agents and publishers, and that kids these days only read Nascar biopics. Yay for being an old fart even in my own generation.