Anecdata for the "spam calling isn’t a problem" assertion. Maybe two of these were "real" calls with real voice mail.pic.twitter.com/Nwu8f4zSeL
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Yep. And I'm not a phone talker, so nearly all calls go to voicemail even when I know who it is (except immediate family.)
Juuuuust now ignored a call and there’s a 1sec static voice mail
A vast amount of spam will generate a sufficient amount of revenue given enough time and gullibility.
I don't mind voicemail. In fact, it made it possible for me to keep my father's last phone call and message to me. 
I’m sorry to hear, and glad you have that. (More general, nothing against VM. Just spam robocalls leaving 1sec VMs.)
Thanks. It's been several years, but I still have that voicemail!
And yes, empty voicemails are a bother. #Delete
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