Two teen boy athletes here too. Both lukewarm about breakfast - unless it’s after a morning workout, in which case they’re very hungry. On normal days, they might grab a waffle with peanut butter or drink part of a smoothie but many days they won’t eat until 10 or so at school. Neither is someone who is particularly sensitive to swings in blood sugar (being hangry has never really been a thing in my house). Their eating schedule during the week is little/no breakfast at 7, morning snack at school at some point (part of the lunch they pack), medium sized lunch around 11, full meal as an afterschool snack around 3, 2nd dinner with us around 7

No and hasn't for years. Both kids stay up very late and have a late dinner. They are not hungry when they get up.
Also, it takes them 5 minutes to get out the door in the morning.

It's important to me that we sit down for meals as a family, and my teens are rarely all home for dinner on a weeknight, so we sit down together for breakfast each morning.

I do require that they come and sit. I don't require that they eat. But all of them are boys and athletes, so if there is food in front of them they generally eat it.

Senior doesn't and complains when we ask him to. I've even found uneaten food in his car when we made him leave the house with something. Junior always eats breakfast.

My son did. Daughter did not. Both athletes. Now as young adults neither do. Unless they were underweight I would not worry about it. They know when they are hungry