Background: Some think that Islam promotes racism because it is pro-Arab due to promotion of things Arabic or Arab customs. Also, some think Islam is pro-black and anti-white due to groups such as the Nation of Islam.
The Quran makes it very clear that the most important differentiator when it comes to people, is that who is most righteous:
O mankind, We created you from a male and female, and We made you into nations and tribes, that you may know one another. Surely, the most honorable among you in the sight of God is the most righteous. God is Knowledgeable, Expert. [49:13]
And from His signs is the creation of the heavens and the earth, and the difference of your languages and your colors. In that are signs for the knowledgeable beings. [30:22]
It should be noted that everywhere in The Quran, the phrase “His (i.e. God’s) signs” are always spoken of positively and serve to remind us of God, and are intended for those who think/reflect.
And lastly, The Quran portrays Arabs like any other people, some are good and some are bad [9:90, 9:97, 9:98, 9:99, 9:101, 9:120, 33:20, 48:11, 48:16, 49:14].
The primary reason why Arabic is promoted is that the original Quran is in Arabic, thus having knowledge of Arabic is helpful thus often promoted