Vestas Sailrocket
en.wikipedia.org
en.wikipedia.org
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.
https://syro.co/en/speed-record/
The syroco design seems wildly unstable and just a simulation really. SP80 has a boat in the water