Board Thread:Questions and Answers/@comment-20551-20190506042615/@comment-246292-20190506120643

The idea is that most existing characters that appeared again after the Crisis weren't changed enough to warrant a second, separate page. Since they changed so little, if at all, their history sections would be identical to their Earth-One counterparts. It doesn't make sense to duplicate that material on some many pages. The characters who were drastically changed either got separate pages from the start or were split when editors working on those books realized how different they were and split them.