TR: Never in our history has Kapparos necessitated moving hundreds of thousands of chickens in fetid, boiling hot storage crates. There is nothing cruel about the Kapparos itself. The current mode of transportation, on the other hand, is obscene.
By MBP, the claim is that 200 years ago they thought it wasn’t dangerous. Now we think that maybe it is. Everyone agrees that MBP was done. The only question is if it is necessary or was just by way of convenience. And the Mohel still gets the blood in his mouth even if there is a sterile tube in between.