SHANGHAI—China’s months-long regulatory crackdown on an array of private companies has unsettled tech upstarts as well as decades-old firms, ushering in a new, uncertain environment. Top antitrust regulator the State Administration for Market Regulation (SAMR) issued sweeping draft rules on Tuesday governing online competition as the cabinet updated rules for operators of information infrastructure that experts say target data-rich firms. Here are sectors facing tougher regulatory measures: E-commerce Traditional e-commerce has been one of the biggest targets with a record fine of $2.75 billion in April for Alibaba over its “choose one from two” feature that bars vendors from selling on rival sites. Smaller companies also faced fines over issues of consumer rights and labor. In May, rival JD.com was fined 300,000 yuan ($46,000) over false information on food products. In late July, the regulator ordered better protection for workers of food delivery firms. Tuesday’s draft laws are widely expected …