The remaining carbon budget for limiting warming to 2°C with 66% probability was estimated (in 2022) as equivalent to 23 years of (then) current CO2 emissions. It does not seem likely that we will be anywhere near zero CO2 emissions in 19 years. We are heading towards a hothouse Earth without the technology to reverse this on any meaningful scale. So no I don't think humans will be more happy, I think they will be hotter, more underwater and more hungry.

Side note: nobody else seems to have mentioned climate change yet in this thread. The fact that we are currently in the process of determining, through our CO2 emissions, what the medium to long term future of human society looks like seems...incredibly significant! And yet people don't seem to want to talk about it. Is it ignorance? Or resignation?

Resignation. As you've already pointed out, we're past the point where we could have stopped it. While I continue to try to keep my environmental footprint small, I recognize that the battle is lost.

The event that sealed it for me, was after decades of hearing about how we need to reduce our energy consumption to save our species, someone made an infinite energy pit that financially rewards people for throwing as much energy into the pit as possible. Bitcoin could not have come at a worse time. The modern LLM craze is not helping either but at least that isn't a literal infinite energy pit.

To quote the philosopher Robert Burnham:

  > You say the ocean's rising like I give a shit
  > You say the whole world's ending, honey, it already did
  > You're not gonna slow it, Heaven knows you tried
  > Got it? Good, now get inside

One interesting way to reframe the whole thing is to ask:

"What would happen if we burned all known fossil fuel reserves?"

The results would be truly catastrophic. This framing leads one to understand that carbon-based fuel must end, no ifs ands or buts. I feel like that should be the question asked, as the answer is far clearer than a 1C vs 2C debate.

Carbon capture will become feasible once we have cheap energy. Building fusion reactors is an engineering problem (AI can help), and the cost of building them is mainly dominated by labor instead of raw materials, which humanoid robots will drive to near zero. AI could of course go very wrong, but it will make environmental problems seem trivial.