DMCA letter sounds like small potatoes when we talk about letting random people write stuff to your disk space and using your bandwidth.
Can you elaborate on what big potatoes you're seeing? Genuinely asking. The Android app, for example, writes everything to the app's storage, and runs only when your phone is plugged-in and is connected to wifi. To me that generally means "when I'm sleeping". What's the big potato in this scenario?
japanese people have been doing this with their darknets for decades and they are fine
This is also known as "Hosting" which, I found amusing.