As always in economics, it's a question of price vs. alternatives and substitution effects.
Aluminum is a good, abundant conductor that can replace copper in most electric applications, with some loss of volume density but improved mass density. Copper-clad-aluminum wires, which combine the stable connectivity of copper with the low weight and price of the aluminum, are becoming standard in aero and trickle down into the automotive and construction sector. High power solid state devices vastly reduce the material needs for electric sub-stations. There are also traditional uses of large quantities of copper, such as roofing and plumbing, which are probably much more price sensitive than electric systems, and will switch to alternatives such as PEX pipe and alternate roofing materials.
So there is a complex web of price inflexion points and substitutes that kick in as the price rises; the energy transition will be just fine.
You handwave physics away. Replacing copper with aluminium in an electrical motor requires in fact development of new motor, with worse efficiency. So motors and generators are going to be more expensive either way. Replacing conductors needs bigger conduits, etc.
The copper piping is already being phased out in favor of plastics, roofing wasn't never really widespread, at least here it was used only on historical buildings. The grid has already been using aluminium whenever possible, including large transformers. Despite all that and despite perfect recycling, demand for copper is rising.
It's diferent from batteries where there's still ample reserve between state of art and physical limits. So they can be easily substituted and price inflexed away.
Aluminum is a good, abundant conductor that can replace copper in most electric applications, with some loss of volume density but improved mass density. Copper-clad-aluminum wires, which combine the stable connectivity of copper with the low weight and price of the aluminum, are becoming standard in aero and trickle down into the automotive and construction sector. High power solid state devices vastly reduce the material needs for electric sub-stations. There are also traditional uses of large quantities of copper, such as roofing and plumbing, which are probably much more price sensitive than electric systems, and will switch to alternatives such as PEX pipe and alternate roofing materials.
So there is a complex web of price inflexion points and substitutes that kick in as the price rises; the energy transition will be just fine.