You are absolutetly correct and if the "do not call" list was a product of the FCC, then there would not be any debate, at least with regard to regulatory authority. The problem is that the "do not call" list was created by the FTC, not the FCC, and Congress has never given the FTC the express authority to do what it has done, although Congress has given the authority to the FCC, which has stonewalled for the last 11 years.
On February 13, 2003, the Congress passed the Do Not Call Implementation Act, which authorized the FTC to collect fees from sellers and telemarketers to "implement and enforce the provisions relating to the 'do-not-call' registry." The President signed this bill on March 11, 2003. Moreover, on February 20, 2003, the President signed the Omnibus Appropriations Act, which authorizes the FTC to "implement and enforce the do-not-call provisions of the Telemarketing Sales Rule."
I believe Congress did....