FWIW, I don't have a problem with that (I think it's really #42).
Jackie R did more to move professional sports, especially baseball, from the Jim Crow era to modernity than anybody else. If he fails, he sets back the civil rights movement bigtime, maybe to the point where the late-50s/early 60s civil rights movement doesn't succeed. It think he was THAT important.
Also, Jackie R was a pretty conservative guy politically. Jesse Jackson would be denouncing him if Jackie were alive today.
Doubly right on what his success meant.
However, that does not warrant retiring a number. Only stellar play deserves a retired number and then only for the team for which he played, not the entire sport.