Indian billionaire Mukesh Ambani’s recent purchase of a Rolls-Royce Cullinan — one of the world’s most expensive SUVs at US$1.8 million (S$2.4 million) — was a reminder of the enduring appeal of luxury cars as a status symbol. Such is the passion of Asia’s second-richest man for automobiles that the managing director of the oil-to-telecoms conglomerate Reliance Industries even coughed...