Copper fails due to freezing, corrosion, or movement fatigue. To some extent you can control all these by using the right solder, cleaning off flux, insulating, strapping pipes properly at stub-outs, accommodating thermal expansion, damping water hammer, etc.

Most houses in the US are expected to be replaced after 70-100 years of use. And all in-wall utilities have a finite lifespan. So the critical question is how often they need to be replaced, and how much damage occurs during a failure. In my experience/opinion soldered copper is proven good for 50-100 years typical between repipes, and PEX is probably good for 30-50 years between repipes. Accelerated-aging studies using high temps show it should hold up better than older stuff like orangeburg or CPVC that have clear reliability problems. Unfortunately, modern connections like propress and sharkbite don’t truthfully have enough field service history to know if they’re 20 year fittings or 50 year fittings or 100 year fittings.