Should transgender people use the bathroom that matches their identity?

It would make non-conforming cisgender people more comfortable

Question: Should transgender people use the bathroom that matches their identity?
Position1 of 4›: Transgender people should use the bathroom that matches their identity
Argument‹2 of 4›: It would make non-conforming cisgender people more comfortable

Anyone whose gender presentation does not align with society's conventions would face fewer difficulties.

The argument

If the law dictates that transgender citizens cannot use the restroom of the gender they identify with, it opens to door for cismen and ciswomen who do not have a physical appearance which matches their birth sex to face scrutiny. For example, it could lead to ciswomen who are often mistaken for males due to their masculine features being challenged over their right to use the female restroom. By allowing transgendered citizens to use the restroom of their choice, the law would reduce the margin for confrontation among people whose appearances do not meet the societies narrowly-defined preconceptions. For example, in a Walmart bathroom a cisgender woman was insulted after she was mistaken for a trans woman. The victim of the abuse said she believed the perpetrator singled her out because she had short hair.

Context

Anyone whose appearance deviates from societies narrowly defined conventions of gender can face scrutiny in a public restroom. Cismen with feminine features and ciswomen with masculine features could face difficulties in public restrooms if transgenders are challenged on their freedom to use their preferred restroom.

Premises

[P1]Barring transgender people from the restroom matching their identity opens the door to scrutiny of cisgender people whose appearance does not match society's narrow expectations—such as masculine-featured ciswomen challenged in women's restrooms. [P2] A real case—a short-haired cisgender woman insulted in a Walmart bathroom after being mistaken for a trans woman—shows that allowing free restroom choice reduces such confrontations. [C] Therefore, because it makes non-conforming cisgender people more comfortable, transgender people should use the bathroom that matches their identity.

Counter-arguments

Cis bathroom users have their birth certificates which show their legal sex. Any confrontation could be easily diffused through the production of documentation showing their official, state-recognised sex.

Rejecting the premises

[Rejecting P2] Any confrontation with cis citizens would be easily diffused by showing ID with the individuals sex assigned at birth.