This week's Good Facility is Sidney Street in Cambridge city centre - an example of an (effectively) pedestrianised street, that allows cycling throughout the day, in both directions. This is despite Sidney Street being busy with pedestrians.
These kinds of streets should not form main cycling routes - there should always be attractive and safe alternatives that allow people cycling to avoid areas that are busy with pedestrians - but, pragmatically, cycling does not always need to be banned in these kinds of environments, for instance when the alternatives are poor.