I added the phone number disconnected sound effect to the beginning of my voicemail outgoing message, set my ringer to silent, and set a personalized ringtone to anyone I actually wanted to speak with. That worked okay to get me off most of the lists. When that wasn’t enough to drive all of them away I started answering unknown numbers and fucking with the people on the other end, saying anything to string them along and waste their time with bullshit and lies. That actually worked better than anything else.