Framing learning things you're uninterested in as "learning to get over yourself" is odd. This isn't an ego problem, and dictating personality traits to such an extent is a questionable goal.

It is an ego problem. You will not have the liberty to be choosy over whatever might be in front of you in life. You will have to shovel the shit, figuratively or quite literally in some cases. The sooner you can learn this lesson, the easier life will be for you, and the more helpful you will be to others around you.