Copper doesn't last a lifetime in Florida. Many houses plumbed with copper must be replumbed with plastic, in as little as 15 years. Hard water? I don't know. The houses I build here in Georgia are plumbed with flowguard gold. Faster to install and no waiting for the water to get get hot coming out of a tap due to thermal loss.
Legal nonsense notwithstanding < G > I cannot drink the water from plastic piping. I am well aware that it (plastic piping) is supposed to be "totally odourless" etc, but *I* can taste the plastic, and it disgusts me.
Copper ions however, *are* known to be vital to overall health, and may play a part in retaining hair color.
I don't know about you, but keeping my hair brown matters to those who enjoy it. My younger brother already has bits of grey, but even my mustache is still one colour.
(BTW, I donate my hair so kids with cancer can have wigs).