Are you suggesting that we form separate Sikh regiments in the US Army?
We don't do that. The question is whether a Sikh soldier can be held to standards different from the non-Sikh standing next to him. That leads to trouble.
Now, we do have women held to different standards, so I suppose we could say to hell with standards. Which is likely what will happen.
No, I am not proposing a Sikh regiment in the US army. And Sikhs in the US army have very few disciplinary problems, so if somebody has heartburn with their turban or beard, it would be them that has the problem.
And no, uniformity has little or no meaning, beyond uniforms, because soldiers are tall and short, all races, several religions as well as atheists. Many black male soldiers have “shaving profiles”, caused by Pseudofolliculitis barbae, which means that they cannot shave every day, and even so, their faces are covered by scarring.
Having a turban and beard becomes even less a problem the higher the rank of the Sikh. The last one I saw in the Army was a Master Sergeant, Green Beret, in the Special Forces Reserves.