No material is cheap when it has just been developed. Titanium alloys were science fiction in the 1980s, and now I can find titanium camping forks and mugs for

No material is cheap when it has just been developed. Titanium alloys were science fiction in the 1980s, and now I can find titanium camping forks and mugs for €10. Special steels can also cost a fortune (powder metallurgy, superduplex). There are many more foundries and workshops producing copper alloys than nickel alloys. The supply chain is much simpler and more diverse. Copper recycling is a reality, but nickel alloy recycling is less so. Significant efforts are being made to reduce dependence on rare metals. No one really knows which ones will actually break through in the future. But having more options is always a good thing.