Good e-readers can be bought in Dutch shops for about $100 and they are all made in China. I imagine PLAN could buy them for the equivalent of $10 or $20. Sailors need to have vast amounts of information at their fingertips and the printing ( and reprinting when information changes ) of all kinds of manuals and tables has been a significant expense in navies ( and airlines and many other organisations ). Using electronic documents will likely save much more money than the cost of providing everyone with a decent e-reader. That way they have the information at their fingertips literally compared with having to go to a shelf with books.
Btw after getting rid of some 4000 books we still have more books than are shown in this library.
Even if they do bring in e-readers, I think important stuff like manuals, tables and maps will always been taken in the form of hard copies, even just as a backup.
E-readers are consumer electronics and not designed for military use. I have my doubts about how well they might fair in the kinds of high emissions environment military equipment are often exposed to. Even without taking things like EM blasts from nukes or conventional EM weapons into consideration, normal emissions like those from jammers or even powerful radars might be enough to break e-readers. Then, there are work environment issues, such as exposure to moisture or being dropped to the floor if the ship was caught in rough seas etc.
Even mundane things like forgetting to charge the battery could post issues if your only manual or table was on an e-reader, and lets not forget about possible issues cropping up with software glitches or errors. Just look at the USS Guardian incident. It seems very likely that the ship would have avoided the reef if the crew had manually plotted their course on conventional maps instead of over-relying on their digital map, which turned out to be wrong.