Aaron, sad as it may seem to say, I think George Orwell's imagination simply failed him at the last. As Orwell also wrote:

In the last part, in contrast with disgusting Yahoos, we are shown the noble Houyhnhnms, intelligent horses who are free from human failings. Now these horses, for all their high character and unfailing common sense, are remarkably dreary creatures. Like the inhabitants of various other Utopias, they are chiefly concerned with avoiding fuss. They live uneventful, subdued, 'reasonable' lives, free not only from quarrels, disorder or insecurity of any kind, but also from 'passion', including physical love. They choose their mates on eugenic principles, avoid excesses of affection, and appear somewhat glad to die when their time comes. In the earlier parts of the book Swift has shown where man's folly and scoundrelism lead him: but take away the folly and scoundrelism, and all you are left with, apparently, is a tepid sort of existence, hardly worth leading.

If what Orwell wanted was a sense of "human brotherhood" in place of "swindling", he needed to say more clearly what distinguishes that from the Houyhnhnms or McCarthy's "ants marching in a circle". I am left with the impression that he ducked out a very serious problem and concluded his essay with an applause light, when applause lights were the whole problem behind tepid, watery utopias in the first place.

It's generally easier to point out problems than to find solutions. A sense of human siblinghood, that sounds like a fine thing to me - such a sense as space enthusiasts or existential risk preventers have - but if that's instead of human conflicts, because everyone just wants to help each other out so much...

Did Orwell ever write a story about his world of "human brotherhood"? Was it any good? Why not, if a world like Orwell was envisioning would have more interesting inhabitants than the Houyhnhnms?