That doesn't work (well, not reliably) in the USA because the name/number presented in the caller ID can have little relation to the actual name/number of the c

That doesn't work (well, not reliably) in the USA because the name/number presented in the caller ID can have little relation to the actual name/number of the caller. I wonder if Google is doing anything beyond simply crowdsourcing spam reports based on CallerID, at least for Google Voice numbers since they own that network so may have access to some data (ANI?) that's not normally available on regular phone lines?