It seems impossible to predict. The reason the price would not go to zero would be that, at the new lower price point, newly viable applications are found. What will these applications be? We can only guess.
What are the properties of Nickel? Would we have Nickel pipes and faucets, and Nickel covered cars?
We already do. Several grades of stainless steel use a lot of nickel, and these are used in many applications. Also it is quite expensive which prevents it from being used generally.