That's true. I don't know what to think because I agree with your exact reasoning, but Minwoo also treated Jaehyun like shit and it looks like he's done with it. I also think he recognises that Seojin is willing to provide him with everything he wants i.e love and support. Idk though since Jaehyun clearly still has lingering feelings for Minwoo...
Tbh I want him to end up single at this point, but I don't see that happening. He's way too dependant on his significant other (whoever that'll turn out to be). On one hand, if he ends up with Minwoo it'll leave a bitter taste in my mouth, but if he ended up with Seojin then idk...personally I think Seojin deserves better.

Would you guys be more surprised if Jaehyun ended up with Seojin or Minwoo? Because I honestly don't know what to think anymore.