Why would that matter, if people didn't use it as much, does it mean that it doesn't matter if there were few people?
Because its a copyright infringement case, so existence and the scale of the infringement is relevant to both whether there is liability and, if so, how much; the issue isn't that it is possible for infringement to occur.
It’s very impressive they managed to do such innovation in their spare time while running a newspaper and site
which is irrelevant at this stage. Its a legal principle that both sides can fairly discover evidence. As finding out how much openAI has infringed copyright is pretty critical to the case, they need to find out.
After all, if its only once or twice, thats a couple of dollars, if its millions of times, that hundreds of millions