Hydrofoils have a very high lift drag ratio. You also have to remember the wetted area of the hull produces significant drag too. Lifting most or all of the hull out out of the water can enable dramatically higher speeds, at the cost of stability and complexity. The biggest America's Cup catamarans were roughly the scale of a 7 story apartment building, but were capable of lifting their entire mass on a foil the size of an ironing board. Because of the density of water, foils can generate a lot of force as lift.
