How would one go about using Usenet for pirating? This is the first time I’ve heard about it being used like that and not in old web forums

I have always heard of this but thought it was an urban legend. I’ve never seen my flights change price after I looked them up more than once. And I always check first with Skyscanner and then search those flights with my browser and find them at the same price. Does this actually happen in Europe? Or is it illegal here?

How do you get into a private tracker?