I hate to go all low-tech on y'all, but since we don't even have cell phones, preferring to live "off leash":
Anybody remember answering machines? We still have one!
Every phone call is let to go to the machine, and if we don't know the caller we don't answer. Don't even have to get up off the couch/look away from whatever we're doing for this system to work... and robocalls automatically just drop us off the list if all they get is an answering machine.
You'd be surprised at how effective this has been to far reduce the number of junk calls we get.