I can assure you, little of it is from the doors. My 2007 Audi A6 allroad is 4300 pounds empty according to its birth certificate and the doors on it don’t weigh much at all… Or rather they didn’t till I added noise absorption mats when I replaced the door locks. Yours is newer but a Golf would likely have less built in noise insulation in the doors than an A6 and it might even have aluminium doors since it’s newer. Mine are still steel, but the metal is pretty thin.