polarized mains plugs - do we really need them?

I remember reading a few years back that it was illegal to design a
product that relied on the polarized nature of its plug for electrical
safety (not sure if that was just for the US, or a european country,
or where..). Such a regulation would make sense, what with "cheater"
plugs and outlets that might be wired wrong in the first place.

So do we really need them? It seems that most appliances and devices
that still use polarized (but not three-prong grounded) plugs are
internally "double insulated" or completely isolated via step-down
xformers.
.

Relevant Pages

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