I've always found distortion to be a bigger issue on older films. They had a tendancy to use very loud blary brass on a lot of old film soundtracks too, and that kind of instrumentation sounds terrible with distortion, which the recordings had in abundance. I can't help feel that if they had recorded the sound under the limit, at the sacrifice of having more hiss, we would have a better chance of restoring it to a listenable state today than the dreadfully distorted state it was actually released with. Very old film, pre 1935 or so, tends to have both hiss and distortion.
Also, i'm not sure why, but film sound recordings made in the 50s and before sound a particular way and thats ok, its not good but I don't have too much issue with it. But there is a certain sound to recordings in the late 60s early 70s on a lot of films that really gets to me in a way I can't define. It sort of makes me fall asleep! I find them very hard to concentrate on.