I have this same problem and concern, and it doesn't work to use voicemail because the robocallers end up filling my voicemail within hours of clearing it out.
The most effective way I have found for dealing with it is horrible but it seems to work. A lot of the robocaller people that I actually end up talking to often sound like they are from a particular nation, not naming any names here. I also happen to know many people from the aforementioned country are quite prejudiced against those of another country that shares a border with them, so when I get a call I do my best accent of a person belonging to the other country and start rambling nonsense about how I just immigrated to America, and I own a shop that sales a particular ethnic food and start offering it to them. Usually I get about 3 minutes in and they hang up. So far of everything I've tried, including using the "Remove me from the list" button this has been the most effective way I've experienced of reducing calls.
It may be terrible but it works, and here's the thing every minute they are spending speaking to an irate man of a particular ethnicity is a minute of their time wasted not speaking to someone who is going to talk to them.
P.S
For those who are really curious the countries anonymized about are Scotland and England. ;)
The most effective way I have found for dealing with it is horrible but it seems to work. A lot of the robocaller people that I actually end up talking to often sound like they are from a particular nation, not naming any names here. I also happen to know many people from the aforementioned country are quite prejudiced against those of another country that shares a border with them, so when I get a call I do my best accent of a person belonging to the other country and start rambling nonsense about how I just immigrated to America, and I own a shop that sales a particular ethnic food and start offering it to them. Usually I get about 3 minutes in and they hang up. So far of everything I've tried, including using the "Remove me from the list" button this has been the most effective way I've experienced of reducing calls.
It may be terrible but it works, and here's the thing every minute they are spending speaking to an irate man of a particular ethnicity is a minute of their time wasted not speaking to someone who is going to talk to them.
P.S
For those who are really curious the countries anonymized about are Scotland and England. ;)