DoorDash's CEO says AI-led productivity isn't everything. Bloomberg/Getty Images Tony Xu says AI boosted productivity at DoorDash, but it hasn't yet changed the workforce structure. DoorDash is focused on unifying its tech stack and making all employees AI-capable. Unlike other tech execs, Xu emphasized AI productivity gains without workforce reductions. One tech CEO says AI has not yet changed his workforce structure. "We're seeing a lot of productivity gains right now from AI, about well north of half of our code, probably closer to two-thirds of our code is written by AI today," DoorDash CEO Tony Xu said on an earnings call on Wednesday. "But that doesn't alone articulate how workflows and team setup ought to change." Xu, who cofounded the delivery app in 2013, said the company is in the midst of deciding how productivity gains may change team structures or head count. But two other things come first.…