DataSweeper for Mac. https://datasweeper.app/
I found out that 500GB of my disk were taken by "System Data". Apple is not really helping you to find it... and apps costs $40-80, per year! I managed to clean it up with Claude. 350GB (After Effects was the culprit) of free space in a few minutes. Crazy good... but seeing someone doing the same and loosing 15 years of family photos forever because Claude thought it was "old junk" was scary too.
So? I built something for myself, both safe because you can see what you delete, and cheap because you pay $9 once and can use the app forever.
Hope it's useful for someone else too! I had a tone of fun with the micro-interactions, sound design, and building for the mac ecosystem with Apple intelligence descriptions.