I thought it was this, as i read the same elsewhere, but it seems he is named Hiroshi for a different reason :
"Why is he called "Hiroshi"?
Yoshida: To tell the truth, it's not that we gave him the official name "Hiroshi". However, there is a staff member who has been working with us...well he worked on the development for Final Fantasy XIV, although he's currently the director for Final Fantasy XVI. His name is Hiroshi Takai. He's also my great senior and whenever he streams himself playing, people would go "Go! Go! Hiroshi", or "Hiroshi do your best!" and eventually these people identify Hiroshi with the main character, and it stuck. From there we just went "Well, yeah let's just leave it at that". Just to let you know, he's actually nameless, okay?"
Video here : https://www.youtube.com/watch?v=Zy4PJiwTktg
Found on reddit here : https://www.reddit.com/r/ffxiv/comme...hare&context=3
