Heh, I thought so too :D
 
 
And now, a counter theory: This is Starlight & Trixie’s daughter, Sunburst was just the sperm donor

It was said in the episode she’s never been to Ponyville. Thus an impossibility.

Headcanon accepted

@PonyPon  
Twilight took Celestia’s place, including instructor of the school of magic, something different to the school of friendship, now run by starlight. Luster may know the importance of friendship, but that doesn’t mean she’s interested in it.

Sure, why not.

@Background Pony #44E6  
What the hell could she have been studying that didn’t include the friendships(or acts that were based on friendship) that created the utopia the show’s future is set in?
 
I’m trying not to be mad at this, because it honestly would make sense based on this little evidence, but i need her to make sense character-wise.
 
Is the cycle of alicorns being that bad at explaining(and rampant cronyism) simply unbreakable?

@PonyPon  
She’s Twilight’s student, as Twilight was for Celestia. It’s obvious that she may have spent more time at her school and personal dorm away from her parents most of the time, like twilight did. I don’t suppose Twilight’s parents had tried raising Twilight keeping her from making friends either.

No.

How’d she get away with thinking friendship wasn’t important?