Something I loved about ZSJL is Superman's role, it showed in a beautiful way that he inspires others to do better, that he saves people not just physically, but spiritually. He left a legacy in the hearts of those who witnessed his compassion and self-sacrifice. ZSJL is a film which depicts Superman as a beacon of hope, drawing in those who might otherwise have been lost.
A couple of recent comics DC put out, Adventures of Superman and Superman: Red and Blue had three or four stories each issue. Usually every month at least one story would be focused on someone other than Superman who was inspired by him. That's what ZSJL is.
Cyborg's story is magnificent, and it is also a parallel of Superman's story in MOS.
At first he is hiding from the world, afraid to reveal himself, yet he cannot resist the urge to use his powers to help those in need.
We see him learning to fly, shakily at first, but then bursting into the air with a smile.
His has a argument with his father, who dies before they have a chance to properly reconcile.
Victors dreamscape conversation with the Mother Box is reminiscent of the dreamscape conversation Clark had with Zod, both are asked join the villain, to reject the world that rejects them.
It is the two of them together that finally separate the boxes, they stand facing each other, mirroring each other. Victor is a successor to Clark, an new hero following in his footsteps.
ZSJL is a film which focuses on Superman as an inspirational figure, as a role model. It shows that trying to live up to his example makes us better people. Because ultimately he can't fight our battles for us, he can't fly off the page to help those in need, but he can give us the courage to fight our own battles and remind us we to help those in need. It it the fulfilment of his "S" being a symbol of hope.
Basically it's this: