I think major difference between sticky floor vs wall (obstruction), "walls" are easier to implement. You place at spot, and works at spot. Some magic floor need make sure, player is on it, don't jump over, it blocks action from different angles, just to prevent player to go into small gap. And for what most annoying may be, it prevents player from action, where action can be 100% legal. For example player want jump in parallel to gap, but not jump into gap. Then suddenly player wont be able to do it. As result the wall / obstruction is very simple to implement, and is least bug / issues prone, than some magic floors, which can bite back, in least expected moment during testing.