
He was a mass murdering tyrant for hundreds of years. Um. But sure, just pick and choose when he's "bad enough to hate". They have always been gray or dark complex characters and their development arcs are still in progress. Pretty sure we are only halfway through the story. Narratively it makes sense from a storytelling perspective that they have conflict right now, it means the proper resolution will feel great to read later.

Point is he was on a redemption arc, but the author completely squandered it with this 'conflict.' Any growth we’ve seen feels hollow and false, cause he’s clearly still a violent tyrant. How are we supposed to believe he'll ever be anything else when this is the result after 200+ chapters of "growth".

You're misinterpreting the narrative flow. Character growth isnt linear in complex stories, usually it's tested in the story, usually the character can fail once or a few times, this is to make the growth more hard earned and for the resolution to feel even greater. Also as it seems like we are in the middle of the story, there is still much growth to be had. It only feels like the story is near the end because it's been serialized for almost a decade, but the story is FAR from over, there are so many unfinished plot threads to show for this, and if it ended soon it would instead feel cheap and hastily wrapped up. You can surely expect more to come. The presence of conflict means the story needs to solve it. You cant see how much care has gone into this and expect the author to just ruin it so easily. She has supposedly spent years plotting this before even starting to draw. Let's have faith.
I've started hating Seth. Like enough is enough. 200 chapters of back and forth, and he mutilates the ML just like that. All because he can't stop and think or ask a simple question before turning to violence. Nephtys wasn't even in the mirror and Horus knew. Genuinely not sure he can redeem himself in my book.