There might be a prospect or two, especially if not a Bloom pick up, that Bloom may not rate as highly as another GM.
That’s all it takes for a swap of young for young.
Now, Downs was acquired by Bloom, so it’s doubtful he does not like him a lot, but GMs trade players and prospects the like a lot quite often. Trading someone does not mean you gave up on the guy or think badly of him.