Most trees for lumber and papermills are grown on farms like corn (in the US at least). Industrialized paper making can be harmful to the environment, but so is essentially all industrialized activity. E-waste is more problematic. Most phones don't last much longer 5 years and can't be 100% recycled easily while most paper products are biodegradable.
But people don’t have to buy additional phones for the purpose of reading books. Also, dead tree industry can never achieve a global distribution at the scale of the Internet. Look at it the way cassettes couldn’t ever have achieved what Youtube has been able to do for new artists/music.
Also, contrary to what many people are told, pulp farming in the US is super harmful to the environment. The damage isn’t local to each manufacturer either. You might want to look-up into wikipedia for credible info on this.
