I think a modern human being can watch Fantasia and understand it is a product of its time, and anyone that can't, well the edited version exists from Disney.
Whitewashing these scenes now seems far more offensive to me than watching it with the scenes intact.
My 5 year old would not understand something like that.
I do agree with you though that whitewashing would be, in and of itself, still pretty offensive when taken in the broadest context. Cropping probably would make better sense in that regard.
I'd just really like to be able to watch this new and improved copy of the film with my kid, in a way that we can all just sit back and enjoy it. We can always pop in the Blu-ray, of course, which I suppose it what we'll have to do.