China Mieville and Ursula Le Guin are both up there are authors who have written things that have felt momentous to read.
But I’m not sure either of them could edge out Terry Pratchett as the author whose work I’ve enjoyed going back to time and time again, having read most of Discworld at a more formative age probably helps too.
I’m fairly sure that at this point pirating has been shown to lead to increased sales, even of small scale productions.
Also, no one said that people can’t keep the rights for a while, just that if you don’t let people access those things you don’t get to prosecute them for making the art available.