On Java Edition, parrots fall off of players' shoulders when falling down just 1 block, rather than two blocks. This is a parity issue with Bedrock Edition, as on Bedrock Edition you need to fall 2 blocks for a parrot to fall off your shoulder. The way it works on Bedrock makes parrots an actually moderately usable feature, so for the sake of parity, their behavior on Java should be changed to match Bedrock.