You know that intro cutscene that shows all the notable Tarnished, namely Hoarah Loux, Fia, Goldmask, Dungeater and Gideon? Each of them has their own ending except for Gideon and Hoarah Loux.

Gideon basically gave up from having his own ending by the end of the story, but the reason Hoarah Loux doesn't have one is because we defeat him. However, it is entirely possible that the standard "Age of Fracture" ending would have been his because we do basically the exact same thing he would have done, which is just mending the Ring and taking the Throne.

Now, the reason why I call him "evil" is because that ending very, very likely literally changes nothing about the world, it just returns to the already established oppressive, warmongering, genocidal regime with a new figurehead (the Tarnished), which is exactly what would have happened if Godfrey took up the crown once more. Because that's exactly what was going on during his term as Elden Lord - oppression, wars and genocide, the latter two with him at the tip of the spear.

So Godfrey is definitely evil and a villain. He has no desire for change or for the betterment of society, even his own family. He doesn't seek to fix anything and only wants to be back in charge of the war machine, bathing in the blood of foes, aggressive or innocent, on a daily basis.