One thing I don’t see mentioned, the elasticizers and plasticizers used to make hoses flexible taste terrible (and I’m sure cause cancer according to the state of California). Inert flexible tubing like silicone is very expensive in the sizes used in residential plumbing, not to speak of commercial or industrial. Pipework is intended to last decades undisturbed, if a mouse decides to gnaw on the hose buried in your wall, you have a hell of an insurance claim on your hands. This was a problem with the first generation of PEX also. That being said, not all is rosy in the world of pipe, galvanized builds scale in hot water, CPVC turns brittle, some copper was installed with Lead bearing solder.