my thing abt the gadreel situation is that dean does understand why sam is upset abt it - he hesitated before he made the initial call bc he knew full well that “sam would rather die” (he says this out loud to gadreel lmfao) but he pulls the trigger anyway bc what dean wants overrides what sam wants. “I wouldn’t let you [die], because that’s not in me” / if there’s the slightest sliver of a chance that some crazy stunt that threatens sam’s personhood and violates his boundaries will keep dean’s Sammy by his side he’s going to take it. exactly the same as dean instructing death to put sam’s soul back in with a flimsy membrane holding back his cage trauma.
so the reason dean reacts so negatively to sam’s anger post “road trip” isn’t because he doesn’t understand why sam is angry. if he didn’t understand he wouldn’t be stewing in guilt and leaning on his usual coping methods of drinking and killing without asking questions and drinking some more. he doesn’t understand the sheer depths of the hurt/betrayal that he inflicted on sam, sure, because he is clearly incapable of processing that. but the reason sam’s anger angers him despite his self-centered non-apology apology in the immediate aftermath is because he feels entitled to sam’s forgiveness. because the decision weighed on him and because he’s guilty about the consequences and because he was “stupid for the right reasons” (cas’s irresponsible words lmfao). he’s merely doing his job of Protecting Sam and sam doesn’t see it that way (“you’re certainly willing to do the sacrificing as long as you’re not the one getting hurt”) which is an insult to dean’s pride. “I saved your hide back there […] I’d do it again,” says dean. “you can’t stand the thought of being alone,” says sam.