Well, that’s partly true because miracles are not always necessary to be officially canonized (one example being Pope John XXIII). However, assuming it is always necessary, it still does not mean that the person now has God-like qualities (ie. able to perform the miracle him/herself).
Don’t forget that the apostles could perform miracles, drive out demons, heal the sick, etc, but we never say that they actually performed them, but that God performed the miracles through them.
That is the reality of being a saint, that GOD does HIS MIRACLES through them.