The Death of Daydreaming

The question these think pieces never seem to answer is, "What did phones do that books didn't already do?"

Books are static and expensive? The front page of <insert social media> reliably changes every day for free without you having to make any choices except to consume. With a book, you have to actively go out, choose, and obtain a book, and then put in a reasonable amount of effort to consume the long form content. Many readers will follow that up with active engagement in the form of thinking about it, daydreaming about it, obtaining other media related to it, writing fanfictions, or conversations with friends.

Anyone who was a bookworm before the late 90s will also be familiar with the problem of your consumption rate vastly outpacing your ability to obtain books, leading to more of those alternatives.

It's not like books are a universal positive either though. It's possible to read so much that your ability to be creative suffers, which is what "phone critics" are alleging here. Putting down the research material is a common bit of writing advice.