Why does Tom say Jim has not gone as far in life as one might have expected?

From the text:

In high school Jim was a hero. He had tremendous Irish good nature and vitality with the scrubbed and polished look of white chinaware. He seemed to move in a continual spotlight. He was a star in basket-ball, captain of the debating club, president of the senior class and the glee club and he sang the male lead in the annual light operas. He was always running or bounding, never just walking. He seemed always at the point of defeating the law of gravity. He was shooting with such velocity through his adolescence that you would logically expect him to arrive at nothing short of the White House by the time he was thirty. But Jim apparently ran into more interference after his graduation from Soldan. His speed had definitely slowed. Six years after he left high school he was holding a job that wasn't much better than mine.

From this, we can infer that Jim had his own obstacles and responsibilites. That regardless of his promise, life had dealt him the hand of being a regular guy, rather than the President of the United States.