I don't really find such science fiction pessimistic. In the way this "golden age optimism" is arguably just coddling humans with lies about the harm that they do, science fiction that critically examines the systems being built and suggests ways to repair. Ways to empower. Ways to unify against systemic harms in a way that includes all people. We have the entire solarpunk genre specifically for how humans can build a more unified, equal future.

I also disagree with this depiction of Golden Age science fiction. Ursula Le Guin and Marge Piercy were doing this well during this period.