Forged cranks, having the general shape of the finished product, need centering, cross drilling, do the hubs, snouts, crankpins and mains journals, and you're done, maybe some tuftriding and polishing

Billet cranks are labor intensive, being totally machined from a round bar , or billet blank, the diameter of which must be greater than the throws\counterbalances.

Would be my guess.

Now, about those billet door knobs, steering wheels and columns, mufflers, brake pedals, license plate brackets, etc...............