LISBON, Nov 2 (Reuters) - Mark MacGann, the whistleblower behind the so-called Uber Files, said on Wednesday that the ride-hailing company seemed to be taking steps toward improving its work culture, but that its business model was still "absolutely" unsustainable.The Guardian and Le Monde newspapers reported in July that Uber Technologies Inc (UBER.N) broke laws and secretly lobbied politicians as part of an aggressive drive to expand into new markets from 2013 to 2017. read moreMacGann, who led Uber's lobbying efforts to win over governments, identified himself as the source who leaked the more than 124,000 company files.Uber said in July, in response to the Guardian and Le Monde reports: "We have not and will not make excuses for past behaviour that is clearly not in line with our present values."Khosrowshahi had said gig workers would lose the flexibility they have today if they became employees and that rides would be more expensive."I'm proposing that gig economy companies be required to establish benefits funds which give workers cash that they can use for the benefits they want, like health insurance or paid time off," Khosrowshahi wrote in the op-ed."