how the judging of the sheep and the goats pivoted from
mankind as a whole to a focus exclusively on JW's.
The article that you refer to does not say that but something that you have concluded on your own.
According to this new
light, those who are sheep are those who support Christ's brothers,
either by preaching or,...Logically then, the parable cannot be directed to the world as a whole, as they do not even know who Christ's Brothers
Again, the logic is all yours. Note the parable that is being discussed in the article.
31 “When the Son of man comes in his glory, and all the angels with him, then he will sit down on his glorious throne. 32 All the nations will be gathered before him, and he will separate people one from another, just as a shepherd separates the sheep from the goats. 33 And he will put the sheep on his right hand, but the goats on his left.
34 “Then the King will say to those on his right: ‘Come, you who have been blessed by my Father, inherit the Kingdom prepared for you from the founding of the world. 35 For I became hungry and you gave me something to eat; I was thirsty and you gave me something to drink. I was a stranger and you received me hospitably; 36 naked and you clothed me. I fell sick and you looked after me. I was in prison and you visited me.’ 37 Then the righteous ones will answer him with the words: ‘Lord, when did we see you hungry and feed you, or thirsty and give you something to drink? 38 When did we see you a stranger and receive you hospitably, or naked and clothe you? 39 When did we see you sick or in prison and visit you?’ 40 In reply the King will say to them, ‘Truly I say to you, to the extent that you did it to one of the least of these my brothers, you did it to me.’
41 “Then he will say to those on his left: ‘Go away from me, you who have been cursed, into the everlasting fire prepared for the Devil and his angels. 42 For I became hungry, but you gave me nothing to eat; and I was thirsty, but you gave me nothing to drink. 43 I was a stranger, but you did not receive me hospitably; naked, but you did not clothe me; sick and in prison, but you did not look after me.’ 44 Then they too will answer with the words: ‘Lord, when did we see you hungry or thirsty or a stranger or naked or sick or in prison and did not minister to you?’ 45 Then he will answer them, saying: ‘Truly I say to you, to the extent that you did not do it to one of these least ones, you did not do it to me.’ 46 These will depart into everlasting cutting-off, but the righteous ones into everlasting life.” -NWT
See, it applies to non JW too. spiritual blindness is no excuse. (Assuming that "sheep" means JW kingdom supporters.)
But credit to you relating this article.