Many wonder why Soldier Boy would give Homelander the V1, and I initially wondered the same thing but then I started to analyze things and came to the following conclusions:
- Soldier Boy is immortal but he is completely alone and he is forced to watch as those with whom he can have company vanish into death and he will be alone again, this being an ouroboros serpent that will repeat itself forever for Soldier Boy and this cycle clearly destroys him from within. Everyone he knew died, and those who survived either wanted nothing to do with him (and had justifiable reasons for doing so) like the rest of Payback, Quinn and Bombsight, or simply didn't know he was alive, like Stormfront, and yet they still ended up dying; he's completely alone, and he knows this better than anyone. So it's no surprise that he wants Homelander (who is his son and therefore the only thing he has left in the world) to become immortal, because that way he wouldn't be alone. Even in previous episodes, Sage told him that whether he liked it or not, he would end up growing fond of his son because of it and even in episode 6 when he was talking to Bombsight, Soldier Boy told him that he could take away his powers and his immortality so he wouldn't be alone, which clearly shows that Soldier Boy was projecting himself onto Bombsight at that moment.
- Soldier Boy wanted to honor Liberty (Stormfront) because, from his perspective, she was the only person who hadn't told him she hated him. While I understand the complaints about Soldier Boy telling Crimson Countess she was the love of his life in season 3 and in season 5 he says that now his love was Liberty, it's important to remember that Soldier Boy didn't know Liberty had V1 and was still alive as Stormfront but he assumed she had died years ago, which is why he fell in love with Crimson Countess (and even if he had known that Liberty still alive, she would have been dead anyway) and besides, right after Soldier Boy told Crimson Countess how he felt, she told him she hated him just like the rest of Payback, and that devastated him so, obviously, he's going to cling to the memory of the only woman who, as far as he and we know, never expressed hatred for him, unlike Crimson Countess.
- Surprisingly, Soldier Boy is someone who always keeps his word which aligns with his moral code of how a man should act. We have to remember that in season 3, when he allied himself with The Boys, Soldier Boy did honor his end of the bargain; he was willing to do his part even after learning Homelander was his son. And in this season, he gave his word to take away Bombsight's powers and kept his end of the bargain. So, when he promised to give Homelander the V1, it was very obvious that Soldier Boy would keep his word.
- When they were at Fort Harmony, Soldier Boy locked Homelander in a room filled with uranium and set out to find traces of V1 to destroy it. But after his reunion with Quinn, and after causing Quinn's death due to the truths Frenchie told him, and the breakdown Soldier Boy suffered as a result, Homelander found him and had the opportunity to kill Soldier Boy to avenge his betrayal. He didn't, which confused Soldier Boy, and not only did he not kill him, but he didn't mock Soldier Boy for crying; he simply asked him if he was crying. This made Soldier Boy begin to appreciate Homelander a little more because he hadn't humiliated him or killed him in his most vulnerable moment, unlike Soldier Boy who constantly humiliated Homelander at every opportunity, because of this, he felt he had to make amends and return the favor somehow, and that's why he helped him search for V1 which again aligns with his moral code of how a man should act (if someone does you a favor you as a man must return the favor).
