I think they could have easily demonstrated this via Sukarn. If they had kept the long gap between Sati and Parvati as per the scripture than Sukarn being around would show us just how great the lifespan of his people were; and they could have shown him to be much bigger than the humans of the current era on the show. For example, he would be a sort of giant standing next to the people of Himavan's kingdom. Mahadev could have then not only restored his youth but reduced his size so that he could take part in the proceedings without trampling someone (š).