They is owning he and she. Example:
An athlete knows that they must train rigorously to qualify for the Olympics.
It even happens when the antecedent is named and sexed. Example:
Jacob has a Master of Fine Arts from Iowa. They are working on a novel.
The only thing that marks Jacob as masculine is the name. Baptismal names have long tended to be gender based. By weight of convention, Annunziata, Niamh, Saoirse and Siobhan are female; Jacob, Sixtus, Wulfric and Boniface are male. But nothing in the nature of names themselves precludes Mick Jagger from having been christened Siobhan, or Sinéad O’Connor Boniface.
This is where opportunity may lie. Johnny Cash sang about “a boy named Sue.” Ye and Kim have a son named North; Elon and Grimes have a son named X Æ A-12; I’ve known a Daughter of the American Revolution named Campbell. A greater practice of untraditional naming over time may see future English speakers less constrained by involuntary gender reveals that contribute to canned presumptions..
A linguist has a healthy respect for the features of sound syntax, and number agreement is one of them. Yet I’m mindful that thou, a singular second person, was ditched in favor of you, a plural second person which conveyed greater distinction. It didn’t happen in a day or without resistance. If third person he-she follows suit, giving way to a non-binary, plural they, it will be in the nature of inevitable change. Following where tested usage leads goes with the speakership.
(c) 2022 JMN — EthicalDative. All rights reserved
EthicalDative 
When I hear ‘they’ I usually think of it as defining plural, not singular. I guess I need to retrain my presumptions! Or perhaps ‘it’ could make an appearance? Good to think about this – thank you!
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You have had the exact thought that I have had! “It” would maintain the sanctity of number agreement, sacrificing instead the animate-inanimate contrast. I’ve never seen any sign that this way of avoiding the he-she gender distinction has been considered. I don’t know how this will end up; it seems to me either approach — ‘they’ or ‘it’ — has the potential to create ambiguity in certain contexts. In the near future, at least, I’ll likely adhere to the traditional syntax, which means saying or writing “he” occasionally when gender is unspecified or unknown. Thanks for reading the post and for your insightful comment. — Jim
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