If gold was no longer wanted for investment, its value would go very close to 0, despite utility to industry. Why? Because there's 190,000 tons of it, most of which is being held as an investment. If it wasn't needed for investment any more, then all that becomes available for industry, and now supply absolutely swamps demand.
Jewelry demand wouldn't help, either. If the price of gold went to 0, how much would be used in jewelry? Sure, it's pretty, but being expensive is part of the point.
I think the tensile strength/density might make gold transmission lines a bit crap. Maybe steel core with a gold outer where the AC current flows, but not sure if it would actually be any better than aluminum.
Plenty of applications like transformers where mechanical stress is a non issue. Corrosion resistance is another useful feature that can be applied to a wide range of use cases.
Jewelry demand wouldn't help, either. If the price of gold went to 0, how much would be used in jewelry? Sure, it's pretty, but being expensive is part of the point.