Can we not compare Dean to John Winchester in the parenting department?
It is true that Dean was being a little shit to Jack, but please it would be close to blasphemy if you say that Dean Winchester is John Winchester who was canonically a shitty parent. Dean, for all intents and purposes is not Jack’s parental figure (at least not yet) and Dean is one of the three best parental figures in the entire show , the other two being Jody and Bobby. Dean was a mother and father to Sam. He practically raised him, cooked for him, looked after him, probably made sure that he had the chance to stay in school because he knew how much Sam loved school and took care of him all his life. Dean was Ben’s dad for an entire year and made such an impression on the child that he tried to get Dean and Lisa back together just so that Dean would come back to him. Dean is the one who shares that special bond with Claire and every other teenage kid they meet. Heck he forms a bond with every other kid they meet in a handful of interactions. On the other hand John Winchester was canonically an old drunk who abandoned his children in shitty motel rooms and forced them to grow up in a hazardous environment. John Winchester was the man who wanted to train his four year old son to become the perfect soldier. He was the son of a bitch who destroyed childhoods.
So don’t you dare say that Dean is John, Dean never was and never will be his biological father. I love Jack, I really do and I screamed profanities at Dean when I watched 13.02 but saying that Dean is John is not just the worst insult but also untrue. Dean’s mistrust towards Jack itself is in fact his parental instinct going on an overdrive and nothing else.