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Not entirely. 
There were options for years. Nuclear could have replaced coal and gas plants. Yet, there was a very strong opposition to nuclear by both environmental activists and the oil/gas industry. We sought a 'perfect' solution, rather than a practical one and it paralyzed us. 
It didn't help that politicians kept rolling over backwards for the oil and gas lobby
It’s weird how concentrated efforts by all the worlds governments might actually affect the climate.
But I’m sure there are no lessons to learn from this. >

It was easy to all get together and agree to use alternative refrigerants and aerosols, when cost effective alternatives were really available. It didn't require any significant change in lifestyle or cost for the average consumer. It was easy
Stopping the use of hydrocarbons, on the other hand...