It seems to me that Newton is 'sitting on the fence' and acting as a spectator to the arguments regarding the Person and the Deity of Christ. He writes that he can observe in the early Church (due to the presence of what he calls 'Nazarenes') that two camps existed and accepted one another's presence in the early Church, so he maintains :

The Nazarenes, as Newton explains in this manuscript, did not believe Christ existed before his birth in Bethlehem. Although Newton crossed it out and chose a passive verb instead, his original words “I do not” are revealing. He goes on to point out that those “who believed that Jesus took his beginning from the Virgin Mary” and those “who believed that Jesus was before the world began … conversed together as brethren & communicated with one another as members of the Church catholick till the days of Justin Martyr, without falling out about their different opinions.”

Isaac Newton - Socinianism and the One True God p281

This is a common argument in many matter of division, to suggest that the argument, does not, in fact, matter and that whichever side of the division one may wish to choose makes no difference to one's spiritual state.

All heresies can thus be excused if one can argue that both sides of a division were allowed in the early Church and both parties had mutual fellowship and communion.

Further, the article goes on to state that Newton uses an argument which is also used by Socinians, regarding the terms 'God' and 'Lord' expressed in the Old Testament writings.

But this is not all. In the third (1726) edition of the Principia, Newton added a note on the word “God” that expands his meaning:

Dr. Pocock derives the Latin word Deus from the Arabic du (in the oblique case di,) which signifies Lord. And in this sense Princes are called Gods, Psal. lxxxii. ver. 6; and John x. ver. 35. And Moses is called a God to his brother Aaron, and a God to Pharaoh (Exod. iv. ver. 16; and vii. ver. 1 [sic; 8]). And in the same sense the souls of dead princes were formerly, by the Heathens, called gods, but falsely, because of their want of dominion.182 In equating the term “God” with “Lord” (a word that straightforwardly refers to dominion), Newton once again stresses that the chief characteristic of “God” or “gods” is dominion. This attempt to present the terms “God” and “Lord” as equivalent mirrors the already-quoted lines from the Racovian Catechism on the God of dominion. The position that persons other than the True God can be termed “God” is a also standard Socinian position and it is expressed in the very same chapter of Crell’s De Deo specified in 1714 by John Edwards.

For both Newton and the Socinians, this conception of dominion also explained how the Son of God could be called God and not be “very God” in the Nicene formulation. Three out of the four biblical passages used by Newton in this note are also utilised by Crell for the same purpose in the same chapter of De Deo. 184 Additionally, the point about false and imaginary Gods can be located in similar form in Crell’s Concerning One God the Father. 185 Finally, the argument on the communicability of the term “God”, along with the scriptural references used by Newton in the note on God, can be found commonly elsewhere in the Socinian corpus.

From my reading of this article, I am left with the distinct impression that Isaac Newton believed both Trinitarians and Socinians fellowshipped together in the early Church and that Isaac Newton appears to regard Deity as monotheistic, yet he does not explicitly say so.

It seems from the article that Isaac Newton did not regard himself under any obligation nor did he have any personal motivation in, himself, declaring his own faith regarding Jesus Christ.

He appears to be stating, that it does not matter and therefore he is not going to reveal what he, himself, believes.