I am very sick of all the pointless phone calls where you don’t even end up with the details in writing. People just expect you to pick-up or respond in a moments notice no matter what you’re doing or where you are. I’d rather just cut the feature entirely.
I don’t think this can be done. In me settings I silence all unknown callers so if they aren’t in my contacts I never see the call. They can still leave a message though.