Copyright holders (not synonymous with the authors, btw) don't actually have a right to be the sole distributors of a product for all of eternity. The law says

Copyright holders (not synonymous with the authors, btw) don't actually have a right to be the sole distributors of a product for all of eternity. The law says they do, but it's a dumb law, and you don't have any moral obligation to follow dumb laws. But the authors of this emulator don't even support unauthorized downloading, as far as I know. You can easily play legally obtained games on RPCS3 by ripping them with an ordinary Blu-ray drive.