How useful would mature hovercraft have been in World War II?
Short answerThey would help in niche commando and difficult-terrain landings, but cost and complexity would prevent them replacing mass-produced conventional landing craft.
NotesHovercraft could cross beaches, marshes, and other obstacles that make ordinary landings difficult. That mobility would make them valuable for selected raids and commando operations. Cost and complexity would prevent production on the scale required for a major invasion. Conventional landing craft would still carry the mass of troops, vehicles, and heavy equipment.