We all know the VK used to go from a leather to a chain whip to a longer chain whip with powerups. But then once Rondo game around, it was just the chain whip. Then in pretty much every game excluding the 64 titles and cotm, its a chain whip.
It's easy to see why this happened: the devs saw how pointless it was to let you powerup since the first few candles u hit are powerups, so just keep the whip in one state.
From a story perspective, it makes no sense. Like Simon holding the leather whip at the end of 4, same with Morris in the end of Bloodlines. Then again Simon buys new whips in CVII, so could the powerups just be new whips that they pick up and use instead of the VK? Even then, later Belmont's just end up with the chain whip. Guess the family ditched a leather whip cus they just keep picking up and using a more effective chain whip anyway