The New York Times, with its customary accuracy, has some of his stats wrong--his lifetime total of home runs (not counting World Series games) was 493 (they have 494).
The original Pride of the Yankees movie about Lou Gehrig is worth seeing--no doubt it takes a few liberties with details but it does give you an idea of why he was loved so much by fans.
It is clear from the story that they either did not know or were not telling the terrible nature and prognosis of this illness. There is a comment that he might regain his health after a couple of years!
Thanks. I have seen the movie.