Oh, I really forgot about that, I don't remember at all. But yeah, Yu should've just politely ask about Takamada's family situation and his relationship with his parents to understand it better, instead of jumping into conclusion and giving useless advice without Yu knowing the whole problem/situation.
But let's not hate Yu because he could be super awkward at times and he didn't know how to handle the situation. I believe Yu just wanted to calm Takamada down because he's worried...
Takamada isn't mad at his father, he's mad at his mom for what she has done to them as a family.
He wants to be there for his father and wants their relationship to be better, but his father is so neglected and probably abused by his wife as well that he probably feels like he'd be a burden on his own son.
The mom has been grooming Takamada ((not in the sexual way but as a "perfect trophy child")) since he was born. Forcing him to do things he doesn't want to do all to improve her own image. She married his father 'cause he owns a hospital/has money, while she runs around and has affairs on the not-so-down-low. She's been manipulating and abusing the two of them for so long that it had in-turn ruined the relationship between him and his father.
Yuu lost his father and regrets that they couldn't have spent more time together and has regrets from not being able to talk to him more. He sees that Takamada really wants to be there for his own father, but is quickly discouraged when his father shuts him out.
The dad is not to blame. The mom is. Yu encouraging Takamada to reconnect with the parent he clearly still cares about isn't him being nosy or butting in places he doesn't belong. As a matter of fact, what he said made Takamada realize how much he is cared for now. Now that he has Yu, maybe now he can actually start healing from his trauma.
I hate when non neglected or abused people try to highroad people into making up with their abusive parents. His father clearly was emotionally unavailable for his son in childhood and adulthood, why is it his job to try for reconciliation? (︶︿︶)=凸