If those who wrote and ratified the 14th Amendment had imagined laws restricting immigration - and had anticipated huge waves of illegal immigration - is it reasonable to presume they would have wanted to provide the reward of citizenship to the children of the violators of those laws? Surely not.
Just as the common law derives from ancient precedents - judges' decisions - rather than statutes, baseball's codes are the game's distilled mores. Their unchanged purpose is to show respect for opponents and the game. In baseball, as in the remainder of life, the most important rules are unwritten. But not unenforced.
Popularity makes no law invulnerable to invalidation. Americans accept judicial supervision of their democracy - judicial review of popular but possibly unconstitutional statutes - because they know that if the Constitution is truly to constitute the nation, it must trump some majority preferences.