system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Why did Luke still have the last name of "Skywalker" when they could have changed it?

I understand Leia was adopted so her name changed to her adopted parents. But why did they keep Luke as a known Skywalker? It's obvious that as soon as Darth Vader heard of someone named Skywalker he would have thought about the relationship. Why not name him "Luke Jones"? That way, when he became a known figure to the empire, Darth Vader wouldn't be able to play upon his feelings? ("No, I *am* your father")
gpt
Darth Vader knew Padme gave birth, he just didn't know there were two. So they took the kids, gave one to an influential senator and hid the other one under his real identity with his real family.

Luke was never ment to defeat the emperor, Lea was. With that cover identity Lea was going to end up as an influential, force sensitive,  government official, who better to lead a political revolution?

Luke was supposed to be the one Vader found if he ever went looking for his kid. Obi-Wan kept himself nearby incase this happened.

tl;dr: Yoda and Obi-Wan were throwing Luke under the bus.