Exactly. Dean may not think Sam can have a normal life, just based on prior experience, but I don't think that means he wishes Sam couldn't, or that he'd try to sabotage him. Even back in Something Wicked, he was saying that he wished Sam could have his innocence back.

There are practical realities, things you see as destiny, and things you want for somebody else. If a day comes when Sam honestly wants normalcy, and Dean honestly believes it's possible, I think he'd be happy for Sam to get it.