Hong Kong's Airport People Mover is an automated four car MTR train railway, with no drivers on board, but with full height Platform Screen Doors, and has been operating smoothly since 1998, some Eighteen years on a daily basis. The trains are even branded MTR. It can be made to work, even in an environment where unfamiliar passengers are the norm, as in the case of Hong Kong Airport.
Newer examples of working driverless systems are the Disneyland Resort Line (single line, two stations with a passing loop in the middle) and the newest South Island Line (5 stations, quite DLR-like except they use full-length 23m carriages and 1.5kV overhead power). Passengers really just see them as normal trains.
All of the systems had platform screen doors or platform gates though.