I ran this on a Flask app. The app has no linting issues and decent test coverage. Vulture reported 192 incidences of unused methods/classes/variables/functions, all at "60% confidence" (whatever that means). There might be some legitimately-unused code in there, but this is almost entirely false positives, with the same "confidence".

It seems like people build giant whitelists when using it with Flask, Django, and other frameworks. Given the volume of false positives, it seems like a maintenance burden to me.

Maybe there's some trick to using it effectively, but it's not obvious to me.