Champions either have crowd control abilities or they don’t, making Oppressor pretty ‘y or n'

Then why do we have two masteries for percent magic and armor pen taking up two spaces when they're just as, if not more, binary to pick than Oppressor was? It's literally down to whether you do more magic or attack damage to decide which you choose and if you're going all the way down the Ferocity tree then you HAVE to pick one of them.

Why not just combine them into a mastery that gives percent armor or magic pen depending on whether you have more AD or AP and move Precision over to the ferocity tree so there's a choice of early game or late game damage?