Nah
I think he's just too overprotective.
Although this is manwha and manwhas' plots always twist
True that...
I'm pretty sure he just smothers him and doesn't realize how harmful it is or rationalizes that if he isn't overprotective that his nephew will be hurt. With his medical condition, I doubt he'd beat him. This doesn't seem like abuse we're used to seeing in so many manhwa. I think the uncle genuinely cares about him, but is extremely close minded that his help can end up being hurtful.
Maybe I've been readings too much messed up manga, but I'm getting some baaaad vibes from that uncle