The vaping industry turns 20 this year, but Ira Simeonidis fears the golden age of e-cigarettes is already wafting away. “It’s a bit destroyed,” says the organiser of Hall of Vapes, Europe’s largest vaping trade fair, held in Stuttgart this month. His festival once drew more than 20,000 visitors, who attended talks, partied with DJs and browsed rows of exhibits by renowned designers showing off their latest “mods”, elaborately crafted devices for inhaling nicotine – and other substances of choice. “It was for professional and passionate vapers,” Simeonidis says. “A community thing, to get together, drink beer, vape and see...