For suppliers the point is you don't have to undervolt as a matter of course in the system build, or risk a bios update down the road by the customer will undo your undervolting efforts.
For you, me, and the other enthusiasts that make up maybe 1% of the aggregate market there is little point to them because we are willing to go to all the effort of managing and babysitting the Vcc setting manually in the BIOS.