Yeah that's not been true for about 50 years.

We replaced all our lead, and it's a legal requirement to if you find a lead pipe in a system, replace it no matter what (even in listed buildings) or disable the outputs entirely (the latter is more common in VERY OLD buildings, with people then adding a new system somewhere else, sometimes with exposed pipework rather than having to potentially damage walls.)

We also just don't do hot water tanks any more usually, instead doing on-demand boilers.

Does mean that the hot runs cold for about a minute, but it balances out