Edit - Nevermind..
>AMAB/AFAB is an intersex terminology, for those who were born with ambiguous genitalia. The intersex community is not happy that it is used inappropriately by those whose genitalia at birth was standard for their sex (trans or not). If your genitalia corresponds with your sex, then you are not AMAB/AFAB, as it means “assigned (fe)male at birth”, where “assigned” depicts the the medical personnel’s choice of what sex would be more suitable for this or that particular baby with this or that particular abnormality (intersex conditions are medical abnormalities of fetal development, not a third sex or whatever). For all other babies with normal genitalia there is no assignment, there is an observation of their biological sex (not gender as in gender identity or gender expectations).
>So, please, do not call yourself AMAB if you don’t have an actual intersex condition (doesn’t matter if you are a trans person or not). This is appropriation.
Sex assignment is the official term used for designating a sex to all babies[0] not just intersex ones. As such it is totally correct to use the terms AFAB and AMAB to describe non-intersex trans or even cis people.
The author most likely just has a bone to pick with trans people for using intersex people for their own ends, without sharing their visibility or talking about our issues. Which is a valid grievance, but this is not a valid outlet for it.
AMAB/AFAB means "they said 'it's a boy/girl' when you were born." That's all.
Sources:
* The reply to your link https://medium.com/p/fb8447cffdee/responses/show
* Reddit discussion https://www.reddit.com/r/asktransgender/comments/7glz6x/does...
* This article https://freedominwickedness.tumblr.com/post/34492218525/once...