Weird, I have a number on Google Voice and it is also the number I give out to businesses and post publicly (any people I don't personally know). The robocalls on that number have become so bad in the past year that I gave up and just turned it off so it won't ever ring through to my phone anymore. Which actually is fine, for how I'm using it, as I just go in and check it every now and then (and have email notifications turned on).

It seems like this is a problem that needs to be cut down at the source of the calls, not necessarily at the filtering stage on the receiving end. Aren't most of these robo-callers likely using the same providers/APIs?

I know Twilio doesn't explicitly allow robocallers on their platform, but it's hard to believe that a lot of them are not using Twilio or companies like it to automate their spam anyway. It seems this problem arose when automated / APIs connected to the telephone system were made, like Twilio, not way back when Bell was split up.