[GRLUG] $50K Prize if You Find Way to Block Robocalls

[Tim Schmidt]

And likely to experience about as much success as spam blocking on the
open internet.

In other words, for common folk, very little.  At least without
someone like Google doing the heavy lifting for them.  In which case,
you might as well route everything through google, and let them do it
the easy way.  A solution that works for 5% of the population doesn't
really work at all.