I have two kids, am self-employed (tutoring) in my community, and have many friends and acquaintances are over 40 (from church, for instance). Sending unknown numbers to voicemail has been completely fine in every case. I've never missed an urgent call that I couldn't call right back after I read the voicemail transcription.
By contrast, in December, I had these time-sensitive calls from unknown numbers: airline lost luggage delivery, Amazon delivery who couldn't get in, my kids' doctors, my pharmacy, someone from my accountant's firm, a bank rep, and a few organizations returning my call. December was a typical month, if a bit slow.
In theory, I could get a voicemail and then follow-up, but that would result in significant time wasted for both sides (e.g., calling doctors again or setting up re-delivery), and the total time I spent on dealing with spam calls is ~1 minute (5-10 seconds x 5-10 occurrences).
