About 1-2% of GDP each year could have cut global warming in half over the last 50 years.

That’s a monumental amount of resources but wouldn’t have had a particularly noticeable lifestyle impact. We would likely have had more nuclear accidents, but those are really local events.

The path was basically eliminating coal, home heating oil, plus drastically reducing oil use by adding in road electrical power delivery for cars. The specific implementation would have depended on massive R&D plus either carbon taxes/banning coal, or larger nuclear subsidies.