The chief executive of the world’s largest stock owner says life is about to get a lot harder for companies that fail environmental, social and governance tests set by institutional investors. Nicolai Tangen, who runs Norges Bank Investment Management from Oslo, says the degree to which ESG dictates a company’s prospects is “starting to hit now.” Firms that don’t adapt face a world in which financing will dry up, insurance companies will walk away, employees will defect, social-media shaming will intensify and customers will disappear, he said in an interview. As CEO of Norway’s wealth fund, Tangen oversees about $1...