here we have plastic pipes CPVC they can't corrode like metal pipes.
I have not heard of any home in TV being re-plumbed, to do so would mean tearing out walls and the concrete slab.
You don't get build up of gunk in the pipes here, I have seen homes 15-20 years old without build up having no filters.
I hate to say this but the pipe story is on one used by water softener sales folks sometimes as a scare tactic.
It is unfounded, all you need here is a high quality whole house filter.