In short, no. Entering and exiting the kayak by pushing straight down “locks” the kayak into place on the KayaArm.
We have installed and personally tested a horizontal arm design but instead of helping it is actually a hindrance. As noted in the “Suggested Operating Instructions” while maneuvering in your kayak it is best to not grip the dock or the mast (or any horizontal bar fastened to the mast) until standing and ready to exit.
The technical reason is that static friction between the bottom of the kayak and the KayaArm arm provides much greater stability than dynamic friction. By pushing, pulling or bracing on any fixed objects outside the kayak you cause the kayak to slide on the arm which changes the frictional contact from static friction to dynamic friction. This friction thing is also the reason that the Added Rope Feature  is very effective in increasing stability as it prevents the kayak from sliding on the arm.