Amanpour does an OK job. She presses him on sensitive subjects (press freedom gets top billing, which is good) and lets the subject talk and give his views rather than making it a full-scale back-and-forth (also good journalism), but yes she could have been more critical and brought out more supplementary questions at certain points. Then again, you have to defer when you’re speaking to a country President at some stages.
In the end, we get the views of Maduro and his government on a lot of issues and can compare them against the reality of Venezuela and/or our own opinions. If only for that it’s necessary viewing for anyone into the subject.