Drew Angerer/Getty Images Will Danoff, manager of the $230 billion Fidelity Contrafund, told Bloomberg that there's a "demographic issue" for mutual funds: Gen Z is not very interested in owning them. "We need to appeal to the Gen Z-ers and the younger generation as well," Danoff said.Danoff also lamented selling a large portion of the fund's Tesla stake.Visit Business Insider's homepage for more stories.Will Danoff has managed the Fidelity Contrafund for over 30 years, but he hasn't seen anything like the "demographic issue" facing mutual funds right now, he told Bloomberg in a recent interview.He was referring to the rise of day-trading activity from young market participants, which has thrown many traditional money managers for a loop."We need to appeal to the Gen Z-ers and the younger generation as well, and luckily I think our app is quite good," Danoff said.