Imagine the completed scene with Luke, Biggs and Red Leader, with Red Leader being a youngling who escaped Anakin's wrath:
Biggs: "Sir, Luke is the best bush pilot in the outer rim."
Red Leader: "Skywalker? I knew your father when I was a boy. Real asshole. Killed all my classmates. Good pilot though ... If you're half the man he was ... well, come to think of it, HE is half the man he was. I'll explain after we blow up the Death Star and kill Vader. Meanwhile, don't worry. You'll do well."
Or maybe Red Leader had nothing to do with the Jedi OR the Old Republic. Maybe he was that red-headed kid on Tatooine:
Biggs: "Sir, Luke is the best bush pilot in the outer rim."
Red Leader: "Skywalker? I knew your father when I was a boy. Punk-ass kid weaseled out of slavery piloting a Pod stolen from his own owner. Left all the rest of us and his own mom on that sweltering sand pit while he went off to be a Jedi. Don't worry. You'll do well. Now, let's go play ball."
Luke: Wait, you're from Tatooine too?
Red Leader: Uh, yeah. We're all from Tatooine ... mostly.
Luke: And he went with Obi-Wan when he was only a kid?
Red Leader: Who the heck is Obi-Wan? He went off with some mullethead Jedi named Qui-Gon who conned his slaveowner.
Luke: I'm so confused.
C-3PO: Hey, that's my line.