You are wrong about at least one thing.
"Since no amount of belt-tightening will pull even a single gram of carbon out of the atmosphere or oceans, austerity is no real solution at all."
Nature pulls tons of green house gases out of the atmosphere every year. If we were at zero emission we would see the CO2 concentrations in the atmosphere begin to drop immediately. Austerity is not the solution but it is part of the solution. Calling it austerity is a joke. More properly it would be called ending wasteful and unnecessary consumption.
We don't need better tools we could get to zero emissions with the tools we already have. I am not against better tools, they will make the job easier but we already have plenty of tools to get started. we need to do more not and not wait on better tools. We don't have a lack of tools we have a lack of will.
We should eliminate waste, are you kidding me. Almost all our consumption is what I would consider waste. It is mostly discretionary not necessary.
Until we eliminate all GHG emitting electrical power generation, it is a huge waste using electrical power to pull CO2 out of the atmosphere.
We need to stop waiting on, counting on technology breakthroughs and execute on a plan that starts reducing emission today, this year, next year not 2030, not 2050, today.