Consider whether Uber's FLEX system should be removed

[TedTed]

To the best of my knowledge, Uber never actually claimed to be using this system in production; the paper suggests that FLEX was built with a clear use case in mind, but I don't know if it's an actual deployment or academic work. Private conversations I've had with folks working in the privacy team at Uber suggested that it is the latter. It might make sense to remove it from the list.