Thankfully where I live robocalls only target landlines and rarely cell phones. My telco moved to voip, and since then I have asterisk pbx software running tha

Thankfully where I live robocalls only target landlines and rarely cell phones. My telco moved to voip, and since then I have asterisk pbx software running that only makes the phone ring if the call is from a whitelist of numbers, otherwise it makes it look like the phone is ringing for a while and then goes straight to voice mail. This works well as 99% of the robo dialers detect the voice mail and don't leave a message. If I was getting lots of voicemails I would probably setup IVR prompts to stifle them.