E-Books are a thing, as are libraries, which allow you to borrow a book and return it. You also have the option of buying books second hand and then sell it again or give it away. That is really one of the key parts of degrowth. As soon as you share things, you need less things as a group. Hence the impact is much lower.
Besides a paperback book has a climate impact of 1kg of CO2. The average US American emits 4.6t per year just by driving their car. The impact of reading books is a complete joke against that and again no libraries, no second hand or anything else to reduce the impact.
Also books are really incredibly usefull resources. They are much better at actually explaining more complex ideas, then shorter articles.
So please do not just presume, somebody is going out to buy something. For the most part the big choices an individual can make on personal consumption are housing, transport and diet.