The Department of Transportation’s Chief Counsel said the same thing earlier this year.
Rep. Peter Defazio (D-OR) inserted an amendment in the House bill H.R. 4 for FAA Reauthorization that would require passing a written exam and licensing of all model aircraft and quadcopter pilots, registration of all model aircraft, and establish FAA rules to require identification and presumably location transponders on all model aircraft.
The House bill passed with two contradictory amendments – the above, plus one preserving Section 336 exemptions for hobby model aircraft. The Senate is now debating its own version of the FAA reauthorization bill.