Just to clarify,

Are you suggesting that a diaper fetish, foot fetish, or whatever is more accurately labeled a separate sexual orientation than a fetish?

No. I am suggesting that the mechanism by which fetishes form is the same as the mechanism by which sexual orientations form. The scientific principle of parsimony or occam's razor suggests that there would probably not be two completely distinct mechanisms that would determine - to put it bluntly - what you would get a hard-on for, one for fetishes and one for orientations. My essay suggests how the same mechanism could fulfill both roles.

My main issue with this theory is that it means all people attracted to a certain group of people (BLs, GLs, heteros, etc) have had a similar childhood experience

Not at all. This is just a misreading. The most obvious way for you to see this is to notice that even among the small number of examples, there are two radically different tracks to becoming BL mentioned, one without traumatic childhood sexual abuse and one with. The whole theme of this essay is that the filtering of imprinting through consciousness produces tremendous variation.