Quote from Flamebuster »White had card draw, albeit subpar, early in the game in the form of Truce and Armistice, among others, excluding cantrips. Blue also had direct damage at one point. Black could kill off artifacts (Gate to Phyrexia and Phyrexian Tribute).
It's not that it can't happen, it's just that it's a rare thing and when it does happen then there's usually a catch affiliated with that particular colour's dynamics and philosophy.
Seems you are confusing what are effectively "rare effects" bur incolor pie and what are rare effect that are rare exactly because they were color pie breaks and error designs.
Early magic is experimentation of unexperienced designers, and therefore, full of errors that cannot be taken as precedents for anything in the present or future.