So many things change if Luke actually gets frozen in carbonite. Many more things change if he doesn't survive the process. For instance:
He never finds out that Darth Vader was his father. For that matter, if you experience these events somewhere a long time from then in a galaxy very,very close as a form of entertainment, neither do you.
Vader is never motivated to redeem himself.
No one is there to rescue Han, Leia, and Chewie from Jabba the Hutt.
No strike team is capable of destroying the shield generator on Endor.
The Rebellion is crushed.
The Jedi never return.
Balance is not restored to the Force.
Good thing that Luke had good reflexes!