The "a technological solution" crowd isn't looking for something that requires lots of money to roll out, like renewable energy.

If you count the externalities of nuclear (eventually having to abandon a city every hundred years or so), gas (some pollution, catastrophic climate change), and coal (pollution, catastrophic climate change), wind and solar look really cheap. Hydro can also be useful by creating reservoirs of fresh water for managing drought cycles.

The biggest issue is that we don’t monetize the externalities in the current state.

The biggest issue is that the costs of not changing anything will have to be paid long after the next election, so why do something today?

I always assume humans want their offspring to survive, but COVID taught us that a lot of people will gladly work for our extinction.