Yes! So simple, but effective. Get a call from an unrecognized or "restricted" number? Just hang up without even answering. If it's a real person that has an actual reason for speaking with you and not a robocall, they'll just redial. Tiny bit of inconvenience for them, but...
I do this any time I get a call from someone I don't recognize. Usually I've blocked some kind of spammer, but sometimes it's a legit call from, for example, someone at a doctors office that uses a different number then what you have for them.