BHP's forecast of a 70% increase in copper demand by 2050 suggests a positive outlook for the company, as it is a major player in the copper mining industry. The emphasis on green energy and digital developments aligns with global trends, potentially boosting BHP's revenues. However, the challenges in supply, such as aging mines and declining ore grades, highlight the need for new projects, which could increase operational costs. Overall, the demand growth is likely to positively impact BHP's stock in the short term.