Arn was really underappreciated for much of his career. I think that's in part because he spent so much time in tag teams, he never really made a run at the top tier singles titles. also, because he wasn't flashy. he and Tully were truly one of the all time great tag teams.
I think Arn has suffered from what so many people suffer from when they work primarily in a tag team enviroment where someone else is the "front man", if you will.
Flair pretty much dominated the Horsemen in most promos, and was a key focus in the ring as well, so people tended to overlook Arn.
the fact that Arn understood and accepted his role contributed to this. he wanted to enhance Ric not try and steal any spotlight. He likely could have demanded a push anytime during his career but i think he really liked the dynamic of the horsemen.
that's true. but also Blanchard and Barry Windham had great singles runs before and during their Horsemen tenures that contributed to their higher profiles. Arn never got a big run at the US or World titles, although he held the tag and TV titles quite a lot, sometimes at the same time.
Arn came to the WWE first... and was more over than Flair ever got there.