I grew up watching old Fleischer cartoons from the 30s and 40s, and you'd see characters like Popeye and Superman fighting really racially stereotypical characters. I saw basically every flavor of racial stereotype from as early as I can remember, but I didn't pay any attention to any of that at the time I watched it. It was re-watching them as an adult that made me see what was in the picture. Did it have any negative affects on me, as to how I see different races and cultures? Absolutely not.
The problem with censorship; you are pretending that the time the piece was created, there weren't views like that. I don't see the point in restoring a censored scene, only to change it further. In fact, I never payed any attention to the badly altered scene until it was brought to my attention when I was trying to work on my own edit of Fantasia a ways back.
The problem with Fantasia is the fact that there isn't really any true original version. That film has been hacked and re-arranged from the second it premiered. And knowing how "well" Disney preserves things, it's a wonder we even have the film in it's butchered state. If you're going to restore something, restore the audio. People are trying to hard to preserve the Fantasound, which has always sounded like shit to my ears. I'd like to hear the best possible source used, instead of these heavily scrubbed recordings that sound like a bad phaser on a guitar pedalboard.
I know for a fact that the reel to reel soundtrack from around 57 (I believe) sounds much better than any home video release in my lifetime. It's getting your hands on it at a reasonable cost and condition; that is the real struggle.
I really feel like Disney had a good idea when they made Fantasia, but the technology just wasn't there yet.
I don't know what sources Disney has at their disposal, so it's probably unfair for me to dog them, but I've just never seen all that good out of any restoration Disney has done lately.