a planetary catastrophe out of our control
You’re still describing climate change. Science fiction ideas are fun to think about but our own inability to live harmoniously with nature is going to kill us off before any of those problems become relevant.
Uh, nope, you’re putting words in my mouth. It’s not realistic to worry about mitigating that kind of stuff when we can’t even prevent ourselves from cooking ourselves, and several of the things you listed don’t even have plausible technical solutions right now. Nice try, though.