The case for the singular “they” to refer to an individual whose pronouns do not match their biological sex has been made numerous times over.
Grammaticians have long argued over its use. Gender advocates have long pushed for the continued use of “they/them/theirs” pronouns spanning over generations.
If not always, then as much as possible, writers and speakers should avoid gendering their audience or an individual without having certainty of how they identify.
Whenever in doubt, or if meeting someone for the first time, it is best to ask the person to share their pronouns much like one would ask for their name, and to use those when referring to them in and outside of their company. Language is a key to ending gender-based violence.
It is important that all make an effort to use gender-neutral language in spaces that are diverse and new to us. While this change begins to happen among English language speakers, those who are learning English can take a further step in their education and include the singular “they” in their conjugation charts.
Those who are learning languages other than English should use gender-neutral pronouns as well. Not every language will translate the singular “they” but people in any language will create or redefine terms for greater inclusion.
While gender inclusivity is becoming more normalized, it has not spread across all realms of life. For instance, you are more likely to be asked to share your pronouns in a women and gender studies course than inside a class with little time for introductions and so the norm of misgendering or assuming gender continues.
All can make an effort to end this cycle, regardless of region, continent or language we speak.