The solution to this is simple, but would need to be implemented by your provider. Just add a screen, like a voicemail, that requires an action be taken to get

The solution to this is simple, but would need to be implemented by your provider. Just add a screen, like a voicemail, that requires an action be taken to get through to speak to you. Your friend with a new phone number calls, they get a message saying, "Stay on the line one second. If you want to speak to me, hit 445." If they take the action, they proceed to connect the call as normal. Otherwise, you don't even know there was a call. Google Voice already has something like this. But it's too annoying to switch over everything to that, plus I don't trust Google to keep features around and can't use them for something that essential.