Latex paints, particularly gloss and semi-glosses have poor print resistance.
They dry soft, and anything that presses against the paint leaves an impression.
This is particularly problematic for bookcases.
I painted my cases with an interior acrylic latex semi-gloss to match my wall color. As it is, it would have very poor print resistance… but it can be helped.
I top-coated my paint job with 3 coats, sanding between coats, of Minwax Polycrylic, which dries to a clear, hard, print resistant finish.
If you are painting a bookcase, and want to avoid fusing with final coats of polycrylic , a good alternative would be Kelly Moore’s DuraPoxy paint which also dries to a hard, print resistant finish.