Oftentimes the best way to get back at a scammer is by giving them a taste of their own medicine. No one likes having their time wasted, their intelligence insulted, and the feeling of being strung along and tricked.
Since scamming requires the scammer to inoculate themselves against the potential guilt of screwing people over, sometimes the best way to wake them up to the madness is through karmic trolling. Most of the time, this results in an angry outburst and swift end to the call, but for every pattern there is an outlier.
I had another scam phone call at work. You know the ones - "Hello, how are you, sir? Good! I am calling from Microsoft technical support warning about scammers who are trying to take over your computer. OK? We need your IP address." Then further down the line, if you are a dope and believe they are stopping scammers, you give them access to your PC and they delete files or ransom it back to you.