Most lost books weren't lost because they were burned. Ancient manuscripts were usually written on Papryus, which does not last very long. So only the ones that were repeatetly copied survived.

The Library of Alexandria was not destroyed suddenly. It experienced a slow decline over centuries. By the time it completely shut down, it had not been a major center of scholarship for a long time. I suspect that most significant works in the collection would have been copied for other libraries over that long period of decline.

Even more impressive is the percentage of otherwise educated people who don't read, don't care for, and is not even curious for, the ancient era manuscripts that were saved and are readily available.

I think that's even more of a tragedy than the lost in time ones, those are lost to indifference.

Sadly true, and it's not limited to the ancient era. There are tomes from within the past 100-150 years that would shake up most peoples' entire worldview that are readily ignored.

Hell, entire subjects are poo-pooed these days. Dare I say the word 'humanities' around a 'tech' worker?

Lost to indifference, religious or scientific dogma, a lack of curiosity, and even more damaging: a lack of humility.

>Dare I say the word 'humanities' around a 'tech' worker?

I think techies are bimodal. Some (most?) don't get humanities at all, and some are more fervent fans of humanities than many humanities people themselves...

Examples? How would one find such tomes?

Bookstores and libraries would do. Many are also available online for free.

On the bright side, there are likely relatively large caches hidden or lost under the sands and could one day be found in the Middle East and North Africa and dry, rural parts of Europe (like the Dead Sea Scrolls).

Why should there be large caches hidden under sands? Has there really been anything like the Dead Sea Scrolls elsewhere? AFAIK those scrolls were there simply because the sect who wrote or collected them lived in those caves, or nearby. Why would anyone cache scrolls under sand (or even anywhere outside)? Isn't that quite unlikely, as a general rule?

Not under sand but the Villa of the Papyri is the best bet. Potentially thousands of rolls, definitely containing lost works. They just need to solve the xray scan and digital unfolding.

https://en.wikipedia.org/wiki/Villa_of_the_Papyri

The "xray scan and digital unfolding" has been solved.

Here's a short video about the process https://www.youtube.com/watch?v=GduCExxB0vw and here's the related publication: https://www.science.org/doi/10.1126/sciadv.1601247

I've had the pleasure to meet one of the authors of the study at a user meeting of the x-ray scanners they use, since I also work with such machines. It's a fascinating study!

Maybe the hope that some royal library at a suddenly-dried-up-oasis palace that was buried in the sands will someday be uncovered?

Seems a stretch, but I'd watch that movie.

Depending on the materials used you could also find older texts hidden in already known books. "erasing" and reusing pages was cheaper than making a new book from scratch. For example the only surviving copy of the Archimedes Palimpsest was found hidden in a prayer book.

And, for example, how many semi random dudes became world famous philosophers while other completely disappeared

We have a very partial view of the past