If there was not a problem with it why was it changed. Every time you use
a
ground as a neutral you ask for problems. Granted it does not happen very
often. But it does happen.

So you say, but cite an incident.
I know the problem is that if the neutral connection at the breaker box
opens, the chassis is potentially hot. Aside from being unlikely (what is
the last time you had a neutral connection at the breaker box open?) it is
dumb. If the chassis is hot, it is because there is an open circuit. If
there is an open circuit, the appliance will not be working. So, you have
to have an open neutral, not notice the appliance is not working, and be
well grounded (since you will be in series with the appliance.)
Sure, with 50,000,000 such circuits out there, there is probably a problem
now and then, but you probably have a bigger risk of being hit by lightning.

The industry has learn a few things in the last 30 years and all that the
NEC does is set a mininum standard. When followed the installation will be
safe for all concerned.

The ground and the neutral aren't the same thing, but they are the same
wire.

Excuse me, No they are not.
A ground is a non current carrying conductor most of the time. A neutral
carries current and voltage. That is why it is insulated all of the time a
ground can be both insulated or bare.

Sure they are the same wire on my 240 circuits; weren't you paying
attention? Contrary to what you just said, my neutral is not insulated.