The majority of my robocalls come from a spoofed number with my same area code. Luckily, I happen to have an area code from several states away, so all my fake calls have out of state numbers. The odds that spammers spoof my local code is nearly 1:1000, so I am able to answer local numbers without issue. It is a less effective system post-covid because more people are using personal cells and VOIP to WFH.

Depending on the logistics, others might have similar success with a google voice number or the equivalent from a unique area code.

I just ignore unknown callers and tell anyone trying to call me to text instead or send me the number they're going to call from ahead of time. I've never had anyone try to tell me they can't do that and have to call from an unknown number.