The AC75 class is now going very fast as well with foils, over 50kts.
Just recently the 40kt barrier was broken by hydrofoil windsurfers. Fins still have a higher top end but the gap has been closing. I'm not sure what design change will enable foils to be just as fast or if they hit a wall.
I've personally done about 24kts on foil and similar on fin and in some cases it's a bit terrifying in more chop. Others are much faster than that.
