singular they/them has been in use for literally centuries

Even if has been in use since forever, a more appropriate word can be introduced now.

When you have a great programmer working on your project he will be cycled to a new project in 2-3 months. Your new senior developer who silently takes over the project is part time because he’s working on finishing his education.

No one knows how anything works, except that one guy, who left the company half a year ago. That’s how all software development is.