> how many people were actually active netizens at this point in history, able to find the ISO?
One active netizen with a CD writer was enough for an entire school :-).
I don't know what impact this had over sales. Back then (~2001, 2002) I knew people who bought a Dreamcast precisely because they could get cheap games.
My last class in highschool was study hall. I sold a ton of bootlegs and took orders from classmates and even teachers. Made about 50 dollars a day after costs.