I think some of the highest jumps I have seen were on Flexifoil blades and on Rafael Salles first ATK foil kite.
Maybe foils turn slower and are therefore more difficult to jump. You need to go really overpowered. But then, you also need to go very overpowered to make huge jumps with a inflatable. I think it doesn't matter wether it is a foil or inflatable, it depends on the skills of the person. But inflatables are easier to use on the water and respond quicker for transitions so I believe they are at the moment the best choice.