Because the words themselves and the grammatical intricacies of using them are not the topic of this SE.
The linked question above is about whether or not is correct to use what was previously regarded as a third person plural pronoun as a gender-neutral third person single pronoun that refers to human beings (since the gender-neutral third person single pronoun "it" always refers to an object or non-sentient entity)
This is an English Language & Usage question and belongs in the corresponding SE.
If you wanted to ask about what is the proper way of addressing a LGBTQ+ correctly in a social setting, here would be the place. Please also note that the majority of those questions are also very language / region dependant so the adequate tags need to be used.
A few examples of a good question would be:
How to address a LGBTQ+ person if I don't know their gender orientation?
I have a genderfluid colleague, how do I address them correctly?
Then proceed to give more details about the social setting and add the country tag.