The major leagues are simply a difficult place for extremely tall hitters to thrive. In the history of Major League Baseball, according to MLB Network, only 13 players six-foot-six or taller have recorded at least 1,000 plate appearances.
With an enormous strike zone to defend, big guys are particularly vulnerable to the strikeout. Therefore, by far the most common way for them to make it in the majors is by hitting for an inordinate amount of power. Of the 13, three puttered out, recording fewer than three WAR during their careers. The remaining ten have each notched at least a dozen wins above replacement over the course of their respective careers.