Okokokok consider that Morgott tried to become elden lord himself but wasn't willing to burn the thorns and is totally loyal to an order that doesn't give a shit about him and so part of unlocking the Morgott For True King Of Leyndell questline is finding a way to convince him that he deserves better... Or finding enough evidence to convince him that what his mommy really wanted from the Shattering was for someone to kill her.
Yes!! This is absolutely something you'd have to do in the Morgott Takes The Elden Ring And You Become His Elden Lord ending; you'd have to help him realise that, despite his love of the Erdtree and all that it represents, the only way to make things better is to go through it. You'd have to help him realise that he's suffered so much for something that's given nothing back. And he'd be utterly heartbroken... but he has the Tarnished now; someone who loves in return, someone who gives rather than solely taking. That gives him the strength to face these things, accept them, and overcome them.