* Not that long ago people's sole access to papers was through insanely expensive journals, with prices that are absolutely unthinkable for a large portion of the world's population.
* Arxiv sort of changed that and a lot of information is widely accessible, granted you don't live in a country with high amounts of censorship.
* On the subject of the first point, I'd argue that piracy affects the overall situation very little. People who need those papers for whatever reason and need to use them/cite them will be forced to purchase them regardless. Similar to software, movies and so on.
* On a personal note, I don't recall using anything other than Arxiv for the past 8-9 years or so with the exception of one notable example involving a medical paper which was published in another location and it wasn't free. That said I purchased it, even if it set me back around 250 euros iirc. It wasn't work related in any shape or form, it was for personal reasons but I could afford it and it only seemed fair. Generally I like supporting people's hard work even if I can't benefit hugely from it - I bought several books that the authors published for free online, just to support them. Even one I found here on HN.