Telemarketing calls to people on the government no call list are illegal but there doesn't appear to be any enforcement. Telemarketers frequently spoof their phone numbers to avoid being reported. The number you see on caller ID is frequently not the number that is actually calling.
Calls should simply not go through if the callers phone number is not valid. Require phone company's to update their equipment to stop and catch telemarketers. Find out why there is no enforcement and fix the problem. Make it a felony for telemarketers to spoof their phone numbers and/or call people on the "No Call" list.