That would be awesome for advanced users but unfortunately bad for mass ergonomics. A shockingly high percentage have never cracked open the settings page even once.
Why would it be hidden away in some settings instead of right in your face with a nice fat button "Change how my videos are recommended..."? Even beyond that though, most online platforms today offer very limited general customization - and so there's not much reason for users to go digging through settings. They are designed to work primarily with the default configuration, and so that becomes a self fulfilling prophecy.