sp1814, going out on a limb here, but I think the liberalisation of abortion may have something to do with this. In the 'good' old days, people just took babies as they came, though mother nature often spontaneously aborted those with major malformations (apparently this happens a lot). Now, though, mums-to-be have scans and tests to uncover any possible deviation from the norm, and can choose to abort a foetus if it's not pretty 'normal'. Result: a much narrower range of 'normal' attributes, and people with one arm (etc) are much rarer than they once were. On top of that, as we no longer send whole generations off to war, you don't see the terrible wounds that people used to have. There were quite few badly wounded ex-soldiers around in my youth; people weren't shocked. Now, however, almost everyone arrives practically perfect in any way, thanks to quality control, and people have a lower tolerance of 'abnormality'.
I'n not disagreeing with you here, just trying to point out why this may be the case.