It may not be just the shape of a floor holding water.
Any turbulence, even from just subtle undulations where the rope through grommets is, will act as a brake.
How many sailboat racing hulls does one see with imperfections?
A plus for a laced in floor is repair / replacement.
Also, rarely in some pins, the floor rope can be cut allowing water to pass through either freeing the boating instantly or making it easier to unpin it.