The military is only interested with being the most efficient fighting force on the planet. The military is not the place to virtue signal. The fact of the matter is that Mattis is following Trumps executive order by halting new hire's from enlisting. Mattis himself put a freeze on their enlistment back in June.

You can be denied from the military for:

Having Flat feet

Any history of depression

Any history of narcotic use (legal or not)

Poor eye sight

Any history of physical disability

Any history of mental disability

Any history of mental illness

Any history of Respiratory System infections such as pneumonia

The list goes on and on. What people don't understand is that if you've ever gotten transitional surgery or started HRT, You are already on a medical disqualification.

I implore all of you to read this post made by a transgender female on the topic