Do people with disabilities exist so that the works of God should be revealed?

In reference to the previous post, which quotes the biblical John 9:2,

"And his disciples asked him, saying, Master, who did sin, this man, or his parents, that he was born blind?", it’s been pointed out that the following verse, John 9:3,

"Jesus answered, Neither hath this man sinned, nor his parents: but that the works of God should be made manifest in him," suggests that disabled people exist to provide an example, as contrasted with people who exist in and of themselves.

That is a problem for civil rights advocates, who hold that all are born equal, and that the disadvantaged are not second class citizens whose purpose is to be useful to others.

John 9:3 does not fit the message of Jesus of Nazareth, that God is kind, generous, loving, and good; and that heaven cares when a sparrow falls.

The Jesus Seminar has concluded that some of the statements attributed to Jesus in the synoptic gospels (Matthew, Mark, and Luke) were probably not actually said by him; and that none of the statements in the gospel of John were things he said.

There are parts of scripture which are to be rejected, such as the passage from Leviticus below, which sets the rules for what Lincoln called "property in man," (slavery):

[Lev 25:44-46 KJV] 44 Both thy bondmen, and thy bondmaids, which thou shalt have, [shall be] of the heathen that are round about you; of them shall ye buy bondmen and bondmaids. 45 Moreover of the children of the strangers that do sojourn among you, of them shall ye buy, and of their families that [are] with you, which they begat in your land: and they shall be your possession. 46 And ye shall take them as an inheritance for your children after you, to inherit [them for] a possession; they shall be your bondmen for ever: but over your brethren the children of Israel, ye shall not rule one over another with rigour.

Likewise, John 9:3 does not give biblical authority to disability discrimination.