They don't because they don't select for it. They disporotionally push engagement but as far as I know don't have some indians or AI working tirelessly analysing countless videos to categorise them and rank them according to how ragebaity or controversial they are. Those things just rise to the top out of their effort to drive engagement and screentime.
Any alternative that does the same will end up with similar result.
And regardless, even if they don't select for rage-bait, they still refuse to take action against accounts that repeatedly post it, making your interjection largely pointless.