Ml forgave his family cuz they realised their mistakes at last, they realised the way they were biased and neglected their child. They were atlast ashamed of their past acts that they couldn't even make an eye contact w the ml, they know the times they have missed just by lookin at their grandson but u have to understand the society they were living in had shaped up their mind in a discriminated way, the way all ppl behaved in this even the ml. The only sane enough here was mc's mother, mc and the professor who also shaped up his mind after hearing mc's rant abt omegas getting discriminated. Sure the way they behaved will forever will be imprinted on the ml but them apologising and him forgiving was the small and new step towards of the change that might contribute to the betterment of the society rather than making them guilty abt it for their whole life, they can use their remaining time left to contribute for even a small change. Your body can survive even w appendicitis removal cuz it doesn't affect the ongoing body functions much But sure a family or close relationships do
I hate that the ML had to forgive his parents in the end, I hated that the MC wouldn't let that issue go. His parents ABUSED and NEGLECTED him all his life. You shouldn't have to forgive people like that. And don't start with the "but they're family, you have to forgive family, they're the only family you have." I only have one appendix but I still cut that out of me when it became toxic to my body.