that seems to be on purpose because of the potential of violating copyright or until they find a good way to generate more money or until YouTube grows so big t

that seems to be on purpose because of the potential of violating copyright or until they find a good way to generate more money or until YouTube grows so big that will be an unevitable source for video (oh yes it's already that) no revenue, no money to pay them in case you get sued. which is why YouTube LLC still exists independently.