Anyone that has studied a foreign language has likely had to understand the concept of gender. There are things that have been assigned a gender even though an object is incapable of reproduction. This gender exists beyond the name of the object. We do this in the English language, for example someone might say, "The USS Ronald Reagan, she is a fine ship."
Also, we see people that will claim we can do anything or be anything if we put our mind to it. We'll see people say the same thing about gender, they will claim to be any one of 50 genders. This gender may have nothing to do with their biological sex. These people will claim that gender is a social construct that has nothing to do with biology, we've been living in a world that asks sexes to conform to these constructed genders and they will not conform to such constructs because they don't feel they should limit themselves to a binary norm.
I will agree with them to some extent, our language and other societal constructs have placed a gender on a lot of things arbitrarily. In English speaking nations sailors will refer to a sailing vessel as a "she" but other societies will refer to their ships as a "he". We don't have to impose a gender on such things, and if society wished we could certainly construct any of a number of genders to use in language. But because of biology and the differences they impose on our bodies and minds we tend to think in binary him/her, he/she, etc.
Here is where I disagree with these people. If you want to separate the masculine and feminine genders from the male and female sexes then on many levels I have no problem with that. I can say this because we've already done so in many cases by imposing a gender on objects like ships at sea. What we cannot do is impose a sex upon a person. Sex is a biological state. We may have constructed the words to define sex of a person or animal but the difference between the two is undeniable.
Side note: I understand that there are rare cases in which biological sex can be ambiguous, indeterminate, or what not. These cases are rare and also not the topic of this discussion. We are discussing people with normal biological development of one sex or the other but choose to identify with a gender that is contrary to their biological sex.
A person that chooses to live outside the social norms of their biological sex still has a biological sex within social norms. These people need to use the restrooms that coincide with their biological sex.
These transgendered people claim to be uncomfortable using a restroom that is contrary to the gender they chose. These people do not seem concerned that they may be making everyone else that uses that restroom uncomfortable. This is exceedingly selfish and they should know this.
Just because they choose to live a life like someone from the opposite sex does not change what they are. This makes a much sense as a male claiming to be a feminine gender demanding to see an OB/GYN for a medical issue. The wishing that things were different does not make them so.
What boggles me the most is how much time has been spent on this even though this affects one percent of one percent of the population. Why is this even a thing?