Per mass, aluminum is better than copper. That's why modern high voltage lines have aluminum conductors around a steel core, while "advanced conductors" (aka High Temperature Low Sag) densely pack aluminum around a composite core.

https://pv-magazine-usa.com/2023/11/20/reconductor-existing-...

https://haas.berkeley.edu/wp-content/uploads/WP343.pdf#page=...

https://www.entsoe.eu/Technopedia/techsheets/high-temperatur...

It’s better in oxidizing environments.