Two mainland Chinese ride-hailing operators in Hong Kong have backed a controversial plan to regulate the industry by capping vehicle permits at 10,000, a figure the city’s largest American business chamber considers insufficient. In submissions to the Legislative Council on Monday and in recent days, Amap and Didi Chuxing said they supported the Transport and Logistics Bureau’s proposed cap as part of a new regulatory regime scheduled to be passed by lawmakers in July. Amap said the...