We've got a clear cut generation divide if you view Bilbo f'n Baggins as more iconic than Spiderman.
While I don't entirely disagree with the sentiment, I think Bilbo Baggins is pretty popular among the older generation (I was introduced to the Hobbit by my brother who is 10 years older than I).
Either way, the fact remains, I wouldn't call Spider-Man's origin iconic, I would call his character iconic. How he gets to that point is really often bordering on stupid or nonsensical. So if they changed it completely, that's why I wouldn't care. If they do change it though, I definitely agree that it's a sign of caving to something topical. That being said though, that's what 90% of comic books and their movies are about so, whatever.