At least for cuneiform tablets, somewhere I read most of them are utterly boring, mostly inventory and transactions. Maybe you could pass years sifting through it to finally find something valuable.
https://cdli.ucla.edu/?q=news/machine-assisted-translation-c...
But neither do the people who might do something with it, which I guess is why there's little funding for such endeavors. You need somebody with the money and conviction to make the gamble.