Well, in reality, MLB is a much tougher position to play than any other LB position. It's widely considered to be the "quarterback" of the defense. On most teams, the MLB position is not always the most talented LB, but is usually the most experienced.
I do agree that the ratings drop is absurd. I also question why my starting LT is ALWAYS my 2nd best TE!? It's pretty interesting to see a 6'8" 330lb guy rambling down the field!