Modern technology can be used to read damaged texts. I’m not sure, but I think there’s a way to read even charred texts. I would imagine there would be many books in a city such as Pompeii. Were they completely destroyed? Or perhaps are they just buried waiting to be rediscovered? Needless to say it would be very exciting to get back lost Greek and Latin classics.
As an aside, is there a lost work that classicists are most hoping to discover?
There are none from Pompeii that I know of, but, famously, hundreds were found at nearby Herculaneum, another victim of Vesuvius on that same day in 79 CE. They are all from one spot, a luxurious villa with an attached library. The papyrus scrolls are mostly tightly wound and very charred by the fiery and ash-filled destruction of the town. These rolls, famously, have undergone a whole range of attempts, from machines to fluids to gases to Synchrotron X-ray phase-contrast tomography. They are collectively called the Herculaneum Papyri.
Centuries of attempts to read them have, up until now, not met with much success. The difficulties are enormous, but they are preserved in the relatively safe confines of the National Library of Naples. Opening them is inherently destructive, as they typically fall to dust upon such attempts. The ink also quickly disappears once exposed to the air. Current attempts center around scanning the rolls without disturbing them physically, then using powerful algorithms to place the readable letters into a coherent text based on their position in the innards of the mass. Google and the NSF have both thrown some funds at such attempts, which are on-going.
There are strong indications that in this very same villa at Herculaneum are yet-un-excavated chambers which might contain further rooms of the "library." These as of now remain unexplored, mostly (from what I gather) due to the costs involved. Excavation at Herculaneum is very laborious compared to at Pompeii: the fill is very hard and difficult to work with, while at Pompeii it is loose and easy to remove. The villa site at Herculaneum also has some problems with flooding and requires a lot of expensive and complicated pumping. So for now, any further scrolls remain in the ground, while the hundreds of others already removed await a technology or method that can read their contents without destroying them.
Here is a piece from the New Yorker about the scrolls. It is five years old now and some more recent attempts have been made since then, but this piece is very well-written and well worth the read.