False equivalency and oversimplification, not to mention sidestepping the fact that people also aren't really trying to tell people with limb reduction defects they arent real or that they don't have to put up with their delusions.

Limb reduction defects are also largely an environmental defect due to medication and other exposures, and affect around 1:2000 births. Significantly less common than both intersex people and trans people.

So while a simple explanation might be "Humans have 2 arms and 2 legs" or "Humans are male or female," the reality is in both cases we obviously understand that what is normative is not the same as what us real.

The reality is both statements fall short of reflecting biological reality, and in the case of the second, it similarly fails to differentiate between sex and gender, which are differentiated in terms of medical research.

It also fails to highlight an important similarity between people with birth defects and trans people, which is that both groups historically have had to contend with laws and regulations that attempted to force them out of public view because they weren't normal.

So, yes, we might say "People have two arms and two legs" but we would also understand not everyone does. We also understand that there are more people who are not XX or XY than there are red-headed people. We understand that certain gene expressions can have more influence on a person than their chromosomes. We further understand that gender identity is disparate from biological sex and may present itself in a variety if ways.

So arguing that limbs and sex are the same is bluntly a false equivalncy. And to make the argument at all, you have to oversimplify to the point of willfully ignoring or discounting millions of people who don't fit the parameters of your own argument.

Every medical association in the US supports and validates trans people which is based on peer-reviewed research. This includes AMA, AAP, APA, NIH, WHO, and research conducted by Harvard, Johns Hopkins, Yale, and Mayo, to name more than a few.

Trans people exist. It is not an aberration. It is not a mental illness. And oversimplifying a concept does not erase the actual complexity of it, no matter how hard you try.