I often get calls from people I don't know for legitimate purposes.

Spam calls happen but I'm not interested in social credit ratings for callers.

Yes, was just relating my experience - it's just go the the point where I personally opt to play safe. Like everyone I do get calls from people who aren't in my contact list but it was getting silly so I've defaulted to ignoring them and it works for me. Anyone serious is going to be happy leaving a message - which suits me anyway as I spend a large part of my work day in Teams calls.

I too, but I never take them before I've looked up the number. If it's important they'll take my call or call back.