ESB'rs have this ******ed preference for boring fighters, fighters that would run all night and minimize any form of contact. Guy who prefer to take their opponents out of there by KO are often viewed as one dimensional.
I think you are right. The slick boxer tend to 'look' better, look at a highlight of RJJ and you think that he is the GOAT , look at a Monzon hightlight and he looks nothing special until the end of the fight and the other guy looks like he has been run over by a truck.
I don't think slick fighters are overrated. I believe slick fighters are not rated high because not to many fighters can achieve this style. Basically that style requires alot of skill to achieve.
Fighters on the ATG list are of all styles. While many aren't known as "slicksters", most of them had, at the least, solid defense. Boxing is not a Rocky movie and you need to able to avoid shots to be great. Even a guy like Marciano, who gets a rep as being this defenseless crude brawler, was tougher to hit than most give him credit for.