Hmm, reading this reminded me of the movie "Sabrina".

It seems like you have this deep rivalry about your brother and that becomes something you carry on whenever you come across anyone like him. He was always younger than you and observing you as older and more able so he most likely developed his own way of getting attention that eventually came across as more charismatic. Also, he probably practiced on you in what he could do to get your attention or maybe even outsmart you. He remained more playful while you continued to stay nice, but serious. Some of that also has to do with how the oldest child tends to be the child the parents stress over and then the next child comes along and the parents are more relaxed simply because they are used to being a parent and are a bit less stressed.

The oldest child tends to be expected to set an example so often the oldest child doesn't get to have the freedom to experiment like the younger child can. You most likely have a parental type personality to you that developed over time unknowingly "nice, responsible" verses "that's his job so I can explore and be different". You are always going to be more mature than your younger brother.

You most likely have that presence about you that is "grounding" and more thoughtful, the nice guy that others like to have present yet misses out on having that narcissistic freedom to challenge, explore, and not have to be so serious and responsible, and when you want to explore and be careless it doesn't fit in with the charector you unknowingly developed that others see in you.

Two years apart means that your brother came along when you were not ready to have competition. He got to be the baby when you were still a mere baby needing just as much attention that he got. You never got over that challenge if you step back and really look at it objectively.