I think you'd be hard pressed to find a time in history when life was better than it is today. And if you did find one, it would be so long ago than population levels were a fragment of what they are now.
We can't go back. Get that idea out of your head. The question is how can we steer the ship.
I guess if we had foresight we could have prevented the industrial revolution which would had (likely) prevented climate change.
Of course, the industrial revolution was a force of economic pressure, not a decision the world came together and decided on in unity.
So to prevent the industrial revolution would have required a suppression of freedom and property rights unlike has ever existed in history. On a world scale.
Thinking that organising a worldwide migration to another planet is going to be a practical option is as absurd as thinking that moving back to a pre-industrial society is.
To be honest, I'm not convinced anyone will try until a mass extinction is underway anyway, in which case you're only migrating your quota of humans for the rocket's load before the volcanic ash density hits 11 (or whatever).
I think you'd be hard pressed to find a time in history when life was better than it is today. And if you did find one, it would be so long ago than population levels were a fragment of what they are now.
We can't go back. Get that idea out of your head. The question is how can we steer the ship.