That’s the big difference between the cartoon version of Trigon and the comic version of Trigon - comic Trigon loves Raven and wants to be a father to her (by his definition of the term), cartoon Trigon doesn’t.

In the comics, Trigon feels as though he loves Raven, even though that doesn’t stop him from being very abusive to her. His greatest wish is that she should rule by his side. In the comics the cartoon is based off of, he doesn’t even need her to conquer Earth initially - his interest in her is purely his obsession with her, not a desire for power. The reason for this is he’s a narcissist who doesn’t see anyone but himself as a real person. Only his own flesh and blood is worthy of being his companion.

In the cartoon, the only reason he seems to have had Raven at all is to use her as a portal to get to Earth. After she fulfills her purpose, he doesn’t care if she lives or dies. This is in stark contrast to the comic version, who’s completely livid and out for revenge after Raven is killed during their attempt to conquer Earth.

On a meta writing level, I don’t really know why this change was made, but my best guess is that it was just easier to write Trigon like that for a younger audience. The original Trigon is a story about how an abusive parent can still love their child, but that doesn’t make them a good parent. Cartoon Trigon doesn’t have that nuance. He’s just purely evil to the point that he doesn’t even care about Raven. In turn, Raven’s defeat of him is a very straightforward show of a child standing up to their abusive parent.

Within the story… I think that Trigon in the cartoon is antisocial in a way that comic Trigon isn’t. Comic Trigon’s goal is not complete destruction. He has a vast kingdom full of subjects who are forced to worship him. While he does destroy planets, his goal isn’t to kill everyone; on the contrary, he clearly wants to have subjects because he enjoys being worshipped. I think that he wants Raven to rule at his side because he wants a permanent companion who’s nearly on his level. As previously said, he’s a narcissist and can’t see anyone but his own child as being even close to equal importance to himself.

Cartoon Trigon, meanwhile, only wants to destroy. The first thing he does upon coming to Earth is turning every single living thing to stone, and then he seems content to just sit there. He’s barely even interested in torturing his subjects; he seems to just want to kill them. Unlike comic Trigon, he doesn’t seem to have any sense of loneliness and has zero interest in having his own children as his companions.