Ummmm, with what you wrote, you can't be outraged with it. It STARTED as a file grabber, but TURNED INTO an mp3 grabber. It wasn't its original intended purpose, but it's what he turned it into.
You wrote "This has its legal uses, such as searching for school notes, other's projects, and so on, but obviously, it quickly became a tool for searching for MP3s (since the school's internal network was much faster than the incoming internet connection). " The whole part in the parens shows it became his intent to grab mp3s. He slipped up, his fault.
If you didn't write the part about it becoming a tool instead of it happens to be able to do that too then yeah, there would be an argument.
plus grabbing school notes and stuff can be considered cheating, depending on what he was grabbing. He should have gotten in trouble with the college too.