Personally, I would put the final theory first - the curriculum most students have experienced does not allow them to practice the kind of reading (or writing) expected of them in college. It predates smartphones. Also, I've had an iPhone longer than any of these students and I can still read.
Opinion | Every generation of professors has complained that their students cannot read. The lament is usually overblown, but data have caught up to anecdote. https://chroni.cl/4vUNFQf
John Warner
The generational collapse in literacy is measurable, persistent, and likely to get worse.
