For regular cellular calls, sure. But carriers make money from the calls to the point they are also selling customer numbers to marketers, so it is completely against the carriers' bottom line to do anything about spam calls. Unfortunate.
But for Facetime calls, Apple has all the caller info. Apple should probably put a feature for users to report a spammer Facetime number so it can be blocked from Apple's end if a number have suspicious activities (eg. random calls of many numbers in short amount of time).