In absolute terms, it is hard to condemn the practice of standing for Holy Communion, since this is the customary posture in Oriental rites validly and licitly and laudably used within the Catholic Church.
But there is a difference between standing for Communion in a Christian tradition in which it has always been thus, and doing so as an innovation in a tradition where kneeling has for centuries been the custom.
To forget this is, ultimately, to forget that ours is an Incarnational religion in which the transcendent Mysteries are expressed and inculturated in multiplicities of times and spaces, that is, within the immemorial traditions and lives of social entities embodied within history.
Cardinal Sarah has beautifully described the insistence with which S John Paul II, dying, weak, and in great pain, insisted on being helped to his knees in order to receive Holy Communion. Strangely, the description is closely paralleled by an account of Henry VIII being advised that, because of the immense agony which his stinking leg ulcers caused him, he need not kneel for Communion. The dying king, despite the schism which he had precipitated, had never lost his belief in the Catholic doctrine of the Eucharist, and he insisted on kneeling, on the grounds that, could he even crawl beneath the earth, he would do insufficient honour to his Sacramental Lord and God.