Bucky Barnes’ story in the Marvel Cinematic Universe (MCU) has been fraught with trauma. He’s arguably suffered the most of all of the characters, alongside Wanda Maximoff. The added focus of the show on the memories of his HYDRA conditioning has already added a chilling element to his story. Everything he knew other than war has been taken from him. Though Wakanda offered momentary peace for him, as Bucky confirmed in the first episode of The Falcon & The Winter Soldier, it was only temporary.
Bucky has a lot to prove, despite his pardon. He has to attend therapy to ensure that he is no longer a brain-washed monster. He has to grapple with explaining himself to his victims’ families and has to accept that Steve Rogers didn’t choose him as a successor. The fact that he is not the symbol the world needs must play on Bucky’s mind along with his desire to escape his life of war. In a lot of ways, his violent past parallels Black Widow’s and we all know how that ends.
Bucky is a man displaced in time like Captain America. His tormented state means that to do anything other than permanently retiring him would be cruel. In a way, Bucky’s past means he deserves to die. The debt he feels he owes the world would make a heroic death in The Falcon & The Winter Soldier merciful, vindicating and even comforting. He would finally be at peace and be remembered for his sacrifice.