There are other ways in which this insistence upon pseudo-equality manifests itself; we can find them (for example) in many aspects of modern education: as when competitive games are forbidden (so that everyone can be a "winner"), or when grading standards are undermined or abolished. We can even see it in the words of a movie villain: Syndrome says, in The Incredibles, "When everyone's super , then no one will be."
This is not to say that there is no such thing as equality among men. That equality is grounded in the fact that we are all created in the image of God. But the fact that we are created in God's image in no way implies that there are no differences among us. Some folks are smarter; others are taller. Some are more handsome or beautiful; others are stronger or faster. It is madness to pretend that these things are not so. With respect to children, it is a disservice to them not to teach them such things: they are going to have to reckon with the fact that there will always be people who are better than they are themselves in some ways or other, and we must all be prepared to accept our own weaknesses with humility and to honor the good things that God has given to others (as well as to us).
St. Thomas insists that there is in fact inequality among men: "Therefore it must be said that as the wisdom of God is the cause of the distinction of things, so the same wisdom is the cause of their inequality" (ST I Q47 A2).
This may be explained as follows. A twofold distinction is found in things; one is a formal distinction as regards things differing specifically; the other is a material distinction as regards things differing numerically only. And as the matter is on account of the form, material distinction exists for the sake of the formal distinction. Hence we see that in incorruptible things there is only one individual of each species, forasmuch as the species is sufficiently preserved in the one; whereas in things generated and corruptible there are many individuals of one species for the preservation of the species. Whence it appears that formal distinction is of greater consequence than material. Now, formal distinction always requires inequality, because as the Philosopher says (Metaph. viii, 10), the forms of things are like numbers in which species vary by addition or subtraction of unity. Hence in natural things species seem to be arranged in degrees; as the mixed things are more perfect than the elements, and plants than minerals, and animals than plants, and men than other animals; and in each of these one species is more perfect than others. Therefore, as the divine wisdom is the cause of the distinction of things for the sake of the perfection of the universe, so it is the cause of inequality. For the universe would not be perfect if only one grade of goodness were found in things (ibid.; emphasis added).As St. Thomas sees it, the fact of inequality does not detract from the perfection of creation, but actually completes it. The upshot is that to deny that there are differences among men is to deny the perfection of the universe.
This is not to say that these material distinctions between us mean that any man is a superior man per se: we are human because we are made in the image of God, and that is something that we all share. Hence it would be horribly wicked to suggest that some man or race of men is somehow sub-human. Formally speaking, we are all men; materially speaking, we all have varying strengths and weaknesses.