Comment by DrScientist

In the end it's it about the money? ie the loss to the copyright holder.

One of the reasons people sharing were gone after is you could aggregate the loss to one lawsuit - the person sharing was responsible for every lost sale - rather than chasing the thousands of individual lost sales, one at once, for each download. Not sure that actually made the best sense from a legal perspective as the sharer wasn't necessarily benefiting - but it was pushed for practical reasons.

In this case I'm assuming Meta downloaded as many pirated books as it could get it's hands on in order to avoid paying for them.

Seems common sense what they did is/should be illegal.