Of course it doesn't (except in some special cases, but that's another debate, and doesn't concern games - see life saving drugs for example).
But the discussion was about DRM and whether they work - IMHO they don't, because the main reason behind piracy isn't accessibility, but too high (price/perceived value). So - limiting accessibility of piracy isn't going to stop it.
Also it would have worked by now if it worked at all.
Also also :) EU did a study in 2013 which found that piracy doesn't really hurt sales, because most people who pirated X and haven't bought it later - wouldn't have bought it anyway. https://cdn.netzpolitik.org/wp-upload/2017/09/displacement_s...