MP3 art shared by napster is different from Knowledge shared by SciHub in that the former was financed privately by record companies while the latter is funded by state taxes (i.e. public money).

At the current state of affairs, Scientific Publishers can be reduced as "curators" of public research publications. They may work very well at that (i.e. reading something from Nature, or from JAMA has its prestige) but there is no reason why they should gate the knowledge behind paywalls. They should offer their "curation/selection" services, dedicated to create lists/collections of scientific articles already published elsewhere for free.